England and Wales High Court (Patents Court) Decisions

Hoechst Marion Roussel Ltd. & Ors v Kirin-Amgen Inc. & Ors [2002] EWHC 471 (Patents) (21st March, 2002)

IN THE HIGH COURT OF JUSTICE
CHANCERY DIVISION
PATENTS COURT

		Royal Courts of Justice Strand, London, WC2A 2LL
		21st March 2002

Mr. Justice Neuberger:

INTRODUCTION

1. This is an application by Kirin-Amgen Inc. and others (“Amgen”):

a. For the amendment of European Patent (UK) Number 148,605 (“the Patent”) by deleting Claims 19 to 25 inclusive therefrom;

b. For a determination that Amgen is entitled to recover damages, costs and expenses from Hoechst Marion Roussel Limited (“HMR”) notwithstanding the amendment of the Patent.

HMR oppose both parts of the application, and contend that the Patent should be revoked.

2. I have considered the Patent on a number of occasions, and in particular in a judgment given on 11^th April 2001. In that judgment, I concluded that, subject to the question of amendment which now has to be considered, the Patent was valid, and that various parties, including HMR, infringed it.
3. The Patent relates to a protein called erythropoietin, or EPO for short, which is produced in healthy mammals in small, but vital, quantities. Its function is to stimulate the production of red blood cells which carry oxygen from the lungs to other parts of the body. The ability to synthesise EPO artificially has substantial commercial and therapeutic implications. Dr Fu-Kuen Lin, who was a member of a research team employed by Amgen, appears to have been the first person to have obtained the amino acid sequence of human EPO, and the DNA sequence of the human EPO gene. He also appears to have been the first person to have used human EPO DNA to enable artificial manufacture, or “expression”, of EPO in certain types of cell, in particular the Chinese Hamster Ovary cell, or CHO cell, and the COS Monkey cell, or COS cell.
4. Naturally occurring human EPO is only obtainable in minute quantities; it can be extracted from urine, and hence is known as urinary EPO, or uEPO. Artificially expressed EPO such as that obtained in accordance with the work of Dr Lin, is known as recombinant EPO, or rEPO. Human EPO is a glycoprotein, i.e. a protein (or polypeptide) with carbohydrate units, or residues, attached. It is during the process of being expressed in a mammalian cell (whether in a human cell naturally or artificially, or in a COS cell or CHO cell artificially) that human EPO becomes glycosylated – i.e. carbohydrate residues become attached to the polypeptide chain, or backbone.
5. Much of the technical background necessary to understand the issues in the main action (as discussed in the judgment of 11^th April 2001 at paragraphs 41 to 131) is not germane to the more limited issues raised on these applications. However, one technique that should be mentioned is SDS-PAGE (discussed at paragraphs 122 to 131 of the earlier judgment). It is a method of assessing the relative molecular weights of different proteins, based on how far they migrate along a gel which is subject to an electric field. The further a protein proceeds along the gel in a particular time, the higher its apparent molecular weight. “Apparent”, because it is a somewhat imprecise exercise, the mobility depending not only on weight, but also on the shape and electric charge of the protein.
6. The Patent as eventually granted contained a Description which ran to over 20 pages of closely printed material interspersed with another 20 pages of tables of polypeptide and DNA sequences. The Description included the following:

a. An introduction which explained that the invention “relates generally to the manipulation of genetic materials and, more particular, to recombinant procedures making possible the production of polypeptides possessing part or all of the primary structural conformation [of EPO]”;

b. Over two pages describing “manipulation of genetic materials”;

c. Over three pages explaining why EPO is “a polypeptide of interest”;

d. A “brief summary” which effectively reproduced the claims, and then went on to explain how vertebrate cells, and in particular COS cells and CHO cells could be transfected with artificially made EPO DNA, which could then be used to express recombinant EPO;

e. A detailed description, which contained twelve Examples, effectively setting out the procedures involved in the claimed invention. In particular, Example 10 explained how CHO cells and COS cells could be transfected with the human EPO gene in a way which enables recombinant EPO to be expressed in substantial quantities.

7. There were 31 Claims in the Patent, as eventually granted. Claims 1 to 11 were to various DNA sequences. Claims 12 to 18 were to cells which had been transfected so as to be enabled to express EPO (and two of the Claims respectively referred to a transfected COS cell and a transfected CHO cell). Claims 19 to 26 were to various different types of recombinant polypeptide, i.e. to EPO which had been effectively manufactured substantially in accordance with the teaching of the Patent. Claims 20 to 25 were dependant on Claim 19. Claims 27 to 29 were process claims, and Claims 30 and 31 were claims to pharmaceutical composition substantially in accordance with the teaching of the Patent.
8. A more detailed description of the contents of the Patent is contained in paragraphs 132 to 183 of my earlier judgment.

A GENERAL OVERVIEW OF THE FACTS

9. The first application for a United States Patent was made on behalf of Amgen on 13^th December 1983, and the three other relevant subsequent applications were made on 21^st February, 28^th September, and 30^th November 1984. (While not of central relevance to the present applications, Amgen made a fifth application on 23^rd October 1987). Amgen’s application for a European Patent was first filed on 12^th December 1984, claiming a priority date by reference to the four earlier US applications. The US Patent applications, like the European Patent application were substantial documents, running to well over twenty thousand words, and including many tables (of amino acid sequences and DNA sequences), Examples, figures, and Claims.
10. As I have mentioned, Example 10 of the Patent was concerned with describing the artificial expression of human EPO in COS cells and in CHO cells which had been transfected with human EPO DNA constructed according to the teaching of the Patent. After the third US application had been made, three paragraphs were added to the end of Example 10 in the fourth US Patent application (made on 30^th November 1984).
11. The three paragraphs (which I shall refer to as the first, second and third paragraphs respectively) at the end of Example 10 of the fourth US Patent application and of the European Patent application were in the following terms:

“A preliminary attempt was made to characterise recombinant glycoprotein products from conditioned medium of COS-1 and CHO cell expression of the human EPO gene in comparison to human urinary EPO isolates using both Western blot analysis and SDS-PAGE. These studies indicated that the CHO-produced EPO material had a somewhat higher molecular weight than the COS-1 expression product which, in turn, was slightly larger than the pooled source human urinary extract. All products were somewhat heterogeneous. Neuraminidase enzyme treatment to remove sialic acid resulted in COS-1 and CHO recombinant products of approximately equal molecular weight which were both nonetheless larger than the resulting asialo human urinary extract. Endoglycosidase F enzyme (EC 3.2.1) treatment of the recombinant CHO product and the urinary extract product (to totally remove carbohydrate from both) resulted in substantially homogeneous products having essentially identical molecular weight characteristics” (emphasis added).

“Purified human urinary EPO and a recombinant, CHO cell-produced, EPO according to the invention were subjected to carbohydrate analysis according to the procedure of Ledeen, et al. Methods in Enzymology, 83(Part D), 139-191 (1982) as modified through use of the hydrolysis procedures of Nesser, et al., Anal.Biochem., 142, 58-67 (1984). Experimentally determined carbohydrate constitution values (expressed as molar ratios of carbohydrate in the product) for the urinary isolate were as follows: Hexoses, 1.73; N-acetylglucosamine, 1; N-acetylneuraminic acid, 0.93; Fucose, 0; and N-acetylgalactosamine, 0. Corresponding values for the recombinant product (derived from CHO pDSVL-gHuEPO 3-day culture media at 100 nM MTX) were as follows: Hexoses, 15.09; N-acetylglucosamine, 1; N-acetylneuraminic acid, 0.998; Fucose, 0; and N-acetylgalactosamine, 0. These findings are consistent with the Western blot and SDS-PAGE analysis described above” (emphasis added).

“Glycoprotein products provided by the present invention are thus comprehensive of products having a primary structural conformation sufficiently duplicative of that of a naturally-occurring erythropoietin to allow possession of one or more of the biological properties thereof and having an average carbohydrate composition which differs from that of naturally-occurring erythropoietin.”

12. Claim 40 included in each of the US Patent applications (which was effectively the predecessor of Claim 19 in the European Patent as eventually granted) was a claim to a recombinant glycoprotein product with the characteristics of human EPO. By the time of the fourth US Patent application, the description of the product was further amended by adding the words “having an average carbohydrate composition which differs from that of naturally-occurring Human erythropoietin”. That limitation to the Claim ultimately proved acceptable to the USPTO: it was included to enable the product claimed to achieve novelty over prior art. It was justified within the four corners of the Patent by the teaching contained in the first, second and third paragraphs of Example 10 (“the three paragraphs”).
13. The European Patent application, which, as I have said, was first filed on 12^th December 1984, was effectively in the same form as the fourth US Patent application. It included in Example 10 the three paragraphs, and included Claim 40 which was a claim to what, in summary terms, may be described as recombinant human EPO which differs from urinary EPO in its “average carbohydrate composition”.
14. Meanwhile, Amgen was seeking the approval in the US from the Food and Drug Administration (“the FDA”), to enable recombinant EPO, manufactured substantially in accordance with the teaching of the Patent applications, to be marketed. An application to the FDA involves at least two stages. At the first stage, the applicant has to submit an Investigatory New Drug Application, known as an IND, and at the second stage it must submit a product license application, or PLA. In these documents, the applicant has to set out information relating to the drug which it wishes to market, to enable the FDA to be satisfied that it is safe and effective. In relation to recombinant EPO, Amgen submitted its IND on the 27^th September 1985 and its PLA some time in October 1987.
15. Also in October 1987, Amgen started litigation in the United States against a Japanese company called Chugai, which was exporting artificial EPO from Japan into the United States. This litigation, “the Chugai litigation”, lasted until 5^th March 1991, when it culminated in success for Amgen. There was a further set of proceedings in the United States which started in about February 1990. These proceedings, “the interference proceedings”, essentially involved a dispute, in the US Board of Patent Appeals and Interferences, as to whether Dr Lin or a Dr Fritsch had first made the breakthrough which led to the claimed invention in the Patent. Dr Lin was backed by Amgen, and Dr Fritsch was backed by another commercial organisation called Genetics Institute (“GI”). The interference proceedings resulted in victory for Dr Lin and Amgen on 3^rd December 1991.
16. During the late 1980s and early 1990s, the United States Patent and Trademark Office (“the USPTO”), was considering the various patent applications filed by Amgen in respect of recombinant EPO. This involved USPTO officials interviewing Amgen personnel, for instance on 30^th July 1986, 20^th July 1988, and 26^th January and 24^th May 1989. On at least one occasion, Mr Odre, Amgen’s general counsel, and Mr Borun, Amgen’s US patent attorney, attended. Following those interviews, Amgen formally responded to the USPTO’s comments and requests on 5^th June 1989. The USPTO initiated a so-called Office Action on 16^th August 1994, which resulted in a response and a proposed preliminary amendment by Amgen during 1995. The process eventually culminated in the USPTO formally granting a patent to Amgen on 20^th August 1996.
17. So far as the application for the European Patent was concerned, the Examining Division of the European Patent Office (“the Examining Division”) informed Amgen’s European Patent Agent, Mr Brown of Forrester & Boehmert, on 21^st January 1988 that there would be a substantive examination, and that the characteristics of the product in Claim 40 (which was in the form which proved acceptable to the USPTO) were “inadequate and imprecise”. Mr Brown and Mr Odre attended an informal interview on 2^nd November 1988. Thereafter, on 21^st April 1989, Amgen filed an amended description with the European Patent Office. On 15^th June 1990, the Examining Division formally communicated to Amgen its decision to grant the Patent, and it was published formally on 25^th July 1990. The Patent contained Claim 20 which was the predecessor of Claim 19 of the Patent in its ultimate form (and the successor to Claim 40 in the original application). As granted, this Claim was to a polypeptide of appropriate conformation and biological properties “characterised by being the product of procaryotic or eucaryotic expression of an exogenous DNA sequence”. Those words were included to distinguish the claimed product from prior art uEPO. Example 10 of the Patent so granted contained the three paragraphs, although they did not, as I see it, need to be invoked to justify Claim 20 of the Patent as granted by the Examining Division.
18. Following the publication of the grant of the Patent by the European Patent Office, oppositions were filed on 24^th and 25^th April 1991. There were five Opponents, each of whom was a substantial commercial organisation, and one of whom was GI or an associate of GI. Amgen responded to these oppositions on 25^th February 1992, and the Opponents replied during the latter half of 1992. The Opposition Division of the European Patent Office (“the Opposition Division”) had a hearing on 25^th and 26^th November 1992, and gave its decision on 20^th January 1993. In principle, the Opposition Division substantially found for Amgen. In so far as it required amendments to the Patent, none of them is relevant for the purpose of these applications. In particular, Claim 20, as accepted by the Examining Division, was also accepted by the Opposition Division. The Opponents appealed this decision, and each of them lodged their grounds towards the end of May 1993, and Amgen responded on 11^th February 1994. After further written evidence and arguments had been filed with the European Patent Office, the provisional view of the Rapporteur was sent to the parties on 19^th July and 25^th August 1994. This resulted in a new Main Request from Amgen to the European Patent Office on 6^th September 1994.
19. The Technical Board of Appeal of the European Patent Office (“the Appeal Board”) then heard oral argument on the appeal between 20^th and 23^rd September 1994, and communicated its decision on 21^st November 1994. During the hearing before the Appeal Board, Amgen conceded that the carbohydrate analysis of the recombinant EPO as contained in the penultimate sentence of the second paragraph could not be supported, in that it was clearly mistaken. In those circumstances, Amgen accepted that the second paragraph should be deleted from Example 10 of the Patent. There were arguments about the validity of some of the contents of the first paragraph, and in particular the second sentence. There were also arguments about the validity of what was then Claim 20, the predecessor of the present Claim 19.
20. During the hearing of the appeal, it became clear to Amgen and their representatives that the Appeal Board was unlikely to be satisfied with the terms of Claim 20 (now Claim 19) as approved by the Opposition Division. Accordingly, in accordance with the normal practice before the Appeal Board, a number of auxiliary requests were made by Amgen during the hearing. These auxiliary requests involved suggested amendments to the claims of the Patent as granted in the Opposition Division. The procedure before the Appeal Board is such that a patentee is normally well advised to put forward as many auxiliary requests as are reasonably possible, because, unless one of them is accepted by the Appeal Board, the claim will be lost. In this case, so far as what is now Claim 19 is concerned, five different formulations were suggested by way of auxiliary request. That which found favour with the Appeal Board was the claim in Auxiliary Request 11, which was a claim to:

“A recombinant polypeptide [having a similar structure to naturally occurring human EPO and with the biological properties of human EPO] and characterised by being the product of eucaryotic expression of an exogenous DNA sequence and which has higher molecular weight by SDS-PAGE from erythropoietin isolated from urinary sources.”

This closing characterisation or limitation was dependent on the teaching of the three paragraphs in Example 10.

21. On 21^st November 1994, the Appeal Board gave its decision, in which it indicated that the claim which is now Claim 19 was acceptable in the form suggested in Auxiliary Request 11. However, the Appeal Board referred the matter back to the Opposition Division, which entertained further written argument between Amgen and the Opponents as to the grant of the Patent. On 26^th May 1997, the Opposition Division decided to affirm the grant of the Patent to Amgen, albeit with modifications, including the deletion of the second paragraph in Example 10 and an amendment to Claim 19 as approved by the Appeal Board (i.e. in accordance with Auxiliary Request 11). Claims 20 to 25 were claims to polypeptides and were contingent on the validity of Claim 19. That decision was again taken to the Appeal Board by the Opponents, but their appeal was effectively dismissed on 26^th March 1998.
22. Accordingly, the Patent as finally granted by the European Patent Office:

a. Includes the first and third of the three paragraphs in Example 10;

b. Excludes from Example 10 the second of the three paragraphs;

c. Includes a claim, Claim 19, to “a recombinant polypeptide” which has appropriately defined sequences and biological properties “being the product of eucaryotic expression of an exogenous DNA sequence and which has higher molecular weight by SDS-PAGE from erythropoietin isolated from urinary sources”;

d. Includes Claims 20 to 25 which are effectively contingent on Claim 19.

23. The validity of the Patent was challenged in this jurisdiction by HMR and a number of other parties, all of whom were alleged by Amgen to infringe the Patent. Following a five week trial, I concluded in my judgment of 11^th April 2001 that the Patent was valid, subject to the proviso that I did not consider Claim 19 to be sufficient (which finding extended to Claims 20 to 25, given that they were contingent on Claim 19). I also held that HMR and various other parties infringed the Patent. My reasons for finding Claim 19 insufficient are in paragraphs 453 to 486 of the judgment of 11^th April 2001. In essence, they were as follows. The apparent molecular weight by SDS-PAGE (“the apparent molecular weight”) of urinary EPO could vary depending upon its source or sources. Recombinant EPO from transfected CHO cells (“CHO rEPO”) would have a higher apparent molecular weight than some urinary EPOs, and the same molecular weight as other urinary EPOs. In those circumstances, it appeared to me that it would be impossible for anyone who had obtained CHO rEPO according to the teaching of the Patent to be sure whether he had obtained a product which was within Claim 19. He might test its apparent molecular weight against that of urinary EPO from a number of different sources and find that it had a higher apparent molecular weight, but he could never be confident that there might not be a urinary EPO which had the same apparent molecular weight as its product. So far as recombinant EPO obtained according to the teaching of the Patent from COS cells (“COS rEPO”) was concerned, I concluded that it had the same apparent molecular weight as, or a slightly lower apparent molecular weight than, urinary EPO, depending on the source of the latter.
24. Concurrently with this litigation, proceedings based on Amgen’s US Patent were brought by Amgen against HMR and others in the United States. Those proceedings, “the US infringement proceedings”, began in April 1997, and they resulted in success for Amgen, but HMR and others are currently appealing that decision. There have also been proceedings in Canada, South Africa and Australia, and, I believe, in other jurisdictions.
25. Amgen are appealing against my finding that Claim 19 is insufficient, and HMR is appealing against my finding that the Patent was otherwise valid, and also against my conclusion that it infringed the Patent. Without prejudice to their contention that Claim 19 is valid, Amgen are making what amounts to a contingent application to amend the Patent so as to delete Claim 19 (and the claims contingent thereon) and for a determination that, notwithstanding the need for this amendment, Amgen should nonetheless be entitled to recover damages, expenses and costs from HMR.

THE PARTIES’ CONTENTIONS

26. HMR contends that there were three errors in the Patent as granted to Amgen by the Opposition Division on 20^th January 1993. Those errors are as follows:

a. The first paragraph of Example 10 described COS rEPO as having a “slightly larger” apparent molecular weight than urinary EPO, whereas there is not and never has been any evidence available to Amgen to support this;

b. The first paragraph of Example 10 described CHO rEPO (and indeed COS rEPO) as having a higher apparent molecular weight than urinary EPO, whereas Amgen knew that urinary EPO had a variable apparent molecular weight which was sometimes equal to that of CHO rEPO (and was sometimes equal to and sometimes greater than, that of COS rEPO);

c. The carbohydrate analysis of recombinant EPO as described in the second paragraph was demonstrably inaccurate.

I shall refer to these errors as error (a), error (b), and error (c) respectively.

27. HMR further contend that each of these errors demonstrates at least a want of skill and knowledge on the part of Amgen and its advisers in drafting the Patent. HMR go further than that, in relation to errors (a) and (b), arguing that there was a lack of good faith on the part of Amgen and their advisers in connection with those errors. It is said that Amgen and/or its agents effectively made up the information in error (a) in order to enable them to contend to the USPTO and to the European Patent Office that recombinant EPO was distinguishable as a product from naturally occurring urinary EPO, which was prior art. For essentially the same reason, HMR says, in relation to error (b), that Amgen withheld information in their possession which showed that, while CHO rEPO had a higher apparent molecular weight than some urinary EPOs, it had the same apparent molecular weight as other urinary EPOs. HMR mounts no bad faith attack so far as error (c) is concerned.
28. HMR relies on the duty of an applicant for a patent, and indeed of a patent agent or patent attorney acting for such an applicant, to give proper disclosure to the European Patent Office. There is no dispute as to the nature or extent of the duty. Mr Borun described it as a “duty of candour”, and I got the fairly firm impression that the duty on a patent attorney in the US is little different from that of a patent agent in the UK and Europe. Mr Brown, whose reliability is not challenged, said that a patent agent should not advance an argument or fact which he knew to be incorrect. However, he also said that he had a duty to his client to advance any reasonable argument which he could.
29. Amgen accept that error (c) was a mistake. Indeed, as I have mentioned, they accepted this in 1994 before the Appeal Board, as a result of which the second paragraph is now deleted from the Patent. Amgen also accept for the purpose of these applications, that, as a result of my judgment of 11^th April 2001, errors (a) and (b) are indeed mistakes, albeit that they are appealing on both points. However, they deny that either error involved any lack of skill or knowledge on their part or on the part of their advisers, and, a fortiori, they deny any want of good faith.
30. Amgen contend that I should amend the Patent by deleting Claim 19, and any consequential claims. Indeed, Amgen argue that, even if I accept HMR’s case on the errors, I should still grant them such relief. Amgen further say that there is no reason for disqualifying them from seeking damages for infringement and costs in the normal way against HMR, in light of my conclusion that HMR infringes Claims 1 and 26 of the Patent.
31. Particularly if I accept that there was any want of good faith on the part of Amgen or their advisers in drafting the Patent, HMR contends that it should not be amended, and that, in such circumstances, it should, indeed it must, be revoked. Even if I decide that the Patent should not be revoked, so that my finding of infringement against HMR stands (subject to it being reversed on appeal), HMR argues that it should not be liable for any costs, damages or expenses because of Amgen’s want of good faith and/or want of skill or knowledge in drafting the Patent.

THE LAW

The Statutory framework

32. The Court has for a long time had the power to amend a patent which, in the absence of amendment, would be partially or wholly invalid. A patent is wholly invalid if all of its claims would be invalid in the absence of an amendment. A partially invalid patent is one which contains only some claims which are invalid, the rest being valid. The effect of refusing to amend a wholly invalid patent would self-evidently be that the patent would remain invalid, and accordingly it would have to be revoked. An amendment of a wholly invalid patent is therefore known as a validating amendment. However, where the Court refuses to amend a partially invalid patent, the position could be said to be more opaque. On the one hand, the invalid part might be said to infect the valid part, and the whole patent would therefore be invalid, and the patent would therefore be revoked in the same way as a wholly invalid patent. On the other hand, it could be that the valid claims should survive. In any event, if and when the Court decides to amend a partially valid patent, the amendment is known as a deleting amendment, because it involves striking out the invalid claims, but not making any amendment to the valid claims.
33. The current powers of the Court grant relief in respect of patents which were not wholly valid when granted is now governed by the provisions of the Patents Act 1977 (“the 1977 Act”), and all references hereafter to sections are to sections of the Act. The 1977 Act was passed, according to its long title, partly to give effect to the United Kingdom’s obligations pursuant to certain conventions, among which is, of course, the European Patent Convention (“the EPC”).
34. Section 63 is concerned with the power of the Court to grant relief in respect of a partially valid patent. So far as relevant, it provides as follows:

“(1) If the validity of a patent is put in issue in proceedings for infringement… and it is found that the patent is only partially valid, the Court… may, subject to sub-section (2) below, grant relief in respect of that part of the patent which is found to be valid and infringed.

(2) Where in any such proceedings it is found that a patent is only partially valid, the Court… shall not grant relief by way of damages, costs or expenses, except where the plaintiff… proves that the specification for the patent was framed in good faith and with reasonable skill and knowledge, and in that event the Court… may grant relief in respect of that part of the patent which is valid and infringed, subject to the discretion of the Court… as to costs or expenses and as to the date from which damages should be reckoned.”

35. Section 72 covers the power to revoke patents, and sub-sections (1) and (4) provide as follows, so far as relevant:

“(1) Subject to the following provisions of this Act, the court… may on the application of any person… revoke a patent for an invention on (but only on) any of the following grounds, that is to say –

…

(c) the specification of the patent does not disclose the invention clearly enough and completely enough for it to be performed by a person skilled in the art;

…

(4) An order under this section may be an order for the unconditional revocation of the patent or, where the court… determines that one of the grounds… has been established, but only so as to invalidate the patent to a limited extent, an order that the patent should be revoked unless within a specified time the specification is amended under section 75…”

36. Section 75(1) deals with the power to amend patents and it is in these terms:

“In any proceedings… in which the validity of the patent is put in issue the Court… may, subject to section 76 below, allow the proprietor of the patent to amend the specification of the patent in such manner, and subject to such terms as to advertising the proposed amendment and as to costs, expenses or otherwise, as the Court… thinks fit.”

37. Article 138 of the EPC is concerned with revocation of a European patent. Article 138(1) sets out the grounds upon which a European patent can be revoked, and they are mirrored in section 72(1). Article 138(2) is in these terms:

“If the grounds for revocation only affect the European patent in part, revocation shall be pronounced in the form of a corresponding limitation of the said patent. If the national law so allows, the limitation may be effected in the form of an amendment to the claims, the description or the drawings.”

38. Although the 1977 Act as expressed in its long title to be intended to give effect to certain international conventions, section 130(7) sets out those sections of the 1977 Act which are expressly intended to give effect to the obligations of the United Kingdom under the EPC. None of the sections to which I have referred are included.

The Issues

39. The nature of the amendment sought by Amgen in the present case is a deleting amendment, because I held that Claims 19 to 25 were invalid, and that the remaining Claims of the Patent were valid. Amgen contend that, in these circumstances, I should grant the amendment because the Claims other than Claims 19 to 25 (“the valid Claims”) will be valid and enforceable whether I grant the amendment to delete Claims 19 to 25 (“the invalid Claims”) or not. However, HMR argues that, unless I grant permission to amend by deleting the invalid claims, the presence of the invalid Claims will infect the whole Patent, and it will have to be wholly revoked.
40. If Amgen are correct, and the valid claims of the Patent would be enforceable whether or not the invalid claims are deleted, it seems to me virtually inevitable that I should grant the amendment to delete the invalid claims. It would prejudice nobody, including any infringer of the valid claims, if I delete the invalid claims in those circumstances, and it would be nothing but a nuisance or worse if the invalid claims remained on the register. On the other hand, if HMR is correct, and refusal to delete the invalid Claims means that the Patent must be revoked, then the questions of revocation and amendment are so closely connected as to be different sides of the same coin.
41. If HMR’s contention on this point of principle is correct, Amgen say that, however strong HMR’s case is in respect of the errors in the drafting of the Patent, it would represent a disproportionate penalty for Amgen if the court refused the amendment. However, relying on what it says is Amgen’s lack of good faith and/or lack of skill and knowledge, but also on Amgen’s conduct, HMR contends that I should refuse the amendment sought by Amgen and revoke the Patent. That raises the question of the proper approach to the discretion of the court to revocation and amendment, if HMR’s case on the proper approach in principle is correct.
42. Assuming that the Patent is not revoked, it is then necessary to consider the proper approach to the granting of relief in light of the provisions of section 63. The parties are agreed that, if section 63(2) does not apply, then the court may (but need not) grant relief in favour of the patentee against an infringer. There was little discussion as to the circumstances in which the court might refuse relief to the patentee if section 63(2) does not apply.
43. The parties are also agreed that if section 63(2) applies, i.e. if I am satisfied that the specification of the Patent was not drafted in good faith or with proper skill and knowledge, then the court has no alternative but to refuse relief by way of damages, costs or expenses. The more difficult question is the proper approach to the question of whether the specification was drafted in good faith and with reasonable skill and knowledge.
44. In this connection, HMR’s case is that if the court is satisfied that any part of the specification whatever has not been drafted in good faith or with reasonable skill and knowledge, then it is bound to conclude that the specification has not been drafted to the requisite standard, because the reference to “the specification” in section 63(2) must be taken as a reference to each and every part of the specification. On the other hand, Amgen’s contention is that the mere fact that one or more parts of the specification can be shown not to have been drafted to the requisite standard does not of itself bring section 63(2) into play automatically. They argue that the court has to ask itself, bearing in mind the findings it has made about the defective parts of the specification, whether, viewed as a whole, the specification has been drafted to the requisite standard.
45. I propose to deal with these questions in turn, albeit that at least some of them clearly cannot be disposed of purely by reference to abstract principle. The answer must depend, at least in part, on the contents of the particular patent and the facts of the particular case.

Partially valid patents: introduction

46. Amgen’s contention, as advanced by Mr Andrew Waugh QC (who appears with Mr Antony Watson QC, Mr Tom Hinchliffe and Mr Colin Birss) is essentially double-barrelled. First, a partially valid patent is valid and enforceable, even without the grant of a deleting amendment (i.e. the deletion of the invalid claims), and therefore there is simply no reason for refusing to grant the deleting amendment. Secondly, the court should strive to construe the 1977 Act so as to comply with the mandatory terms of the first sentence of Article 138(2), which, in the case of a partially valid patent, requires the court to fashion a remedy which effectively retains the valid part of the Patent. HMR, on the other hand, contends that the provisions of the 1977 Act make it clear that the court retains a discretion whether or not to amend a partially valid patent, and that, if it declines to do so, the whole patent must be revoked.
47. If the matter were free of authority, then, in light of the provisions I have cited from the 1977 Act and of the EPC, I would have concluded this issue in favour of Amgen. First, while I accept that the relevant sections of the 1977 Act for this purpose are not included in section 130(7) as having been expressly enacted to ensure compliance with the EPC, it appears to me that one should construe the provisions of the 1977 Act, in so far as it is properly possible to do so, so as to arrive at a result which is consistent with the United Kingdom’s international obligations. In that connection, it appears to me that the first sentence of Article 138(2) of the EPC is intended to be mandatory: not only is that indicated by the words “shall be”, but it is also supported by the contrast with the qualifying nature of the words which govern the second sentence of Article 138(2).
48. Secondly, while the words of section 75(1) appear to give the court a discretion whether to permit an amendment, and that discretion applies to deleting amendments as well as validating amendments, the way in which section 63(1) is expressed strongly suggests that, if the invalidity only affects some of the claims of a patent, the remaining claims nonetheless remain valid. If, in the absence of a deleting amendment, a partially valid patent would have to be revoked, then section 63(1) would have to be treated as subject to an implied qualification, namely that it only applies where the court has exercised its discretion to grant the deleting amendment necessary to remove the invalid claims. The court is slow to imply terms into Statutory provisions.
49. The argument the other way, advanced by Mr David Kitchin QC (who appears for HMR with Mr Richard Meade and Ms Lindsay Lane) essentially rests on section 72(4). This appears to apply to both partially and wholly invalid patents, and the second part of the sub-section suggests that if either type of patent is not amended to cure the invalidity, the patent as a whole should be revoked. I am of the view that, notwithstanding its undoubted force, this point should be rejected. It is true that sub-sections (1) and (4) of section 72 are expressed in discretionary terms: in each case, the court “may” make the revoking order. However, that discretionary power must be construed in the context of the 1977 Act as a whole, and, I would have thought, taking into account the provisions of the EPC. In practice, the way in which the discretion should be exercised is normally pretty clear. Thus, if any of the grounds established in section 72(1) apply to all the claims of a patent and an amendment is not granted, then it is hard to conceive of circumstances where the court would do other than revoke the patent, despite the word “may” in the sub-section. It does not therefore seem to me to be difficult to conclude that, where only some the claims of a patent have been held to be invalid under section 72(1), then, in light of section 63(1) and Article 138(2), the court should, at least in the absence of the most exceptional circumstances, grant a deleting amendment, and thus uphold the patent as amended.
50. Quite apart from this, I consider that section 72(4) is not inconsistent with Amgen’s case. All that it does in relation to an invalid patent is to provide that, if it is not amended within a specified time, then it is revoked: it says nothing about the circumstances in which the court should or should not grant an amendment. In other words, the purpose of section 72(4) in relation to a partially valid patent, could be said to be to ensure that the patentee amends it promptly, so that invalid claims do not remain on the record. Thus, section 72(4) is not concerned with how the court exercises its power in relation to granting or refusing amendments (whether deleting or validating), but with what happens if the patent is not amended. It therefore does not impinge on the issue of whether or how the court should exercise its power to grant deleting amendments, or indeed validating amendments.
51. At first sight, it may be thought to be desirable that, in order to encourage patentees and their advisers to be honest and careful in drafting patents, the court should retain the right to refuse even a deleting amendment, and in those circumstances to revoke the patent. However, I think the answer to that point is to be found in section 63(2). The effect of that section is that, if the court concludes that the patent has not been drafted with the requisite degree of honesty, skill and knowledge, then, even if the patent survives as amended, the patentee is debarred from recovering any compensation or costs in relation to infringement. That should not discourage the patentee from applying to amend: if the court concludes that the patent is only partially valid, it can require a deleting amendment, which must be pursued by the patentee, failing which there is the sanction of revocation in section 72(4).
52. As I see it, section 63(2) is wide in its effect. Even if inaccuracies in the patent do not in fact bear on a particular infringement and have not in any way misled or impinged on a particular infringer, the patentee will nonetheless be unable to recover any damages, costs or expenses in respect of the infringement from such an infringer, unless he can establish that the specification was indeed drafted in good faith and with reasonable skill and knowledge. Accordingly, it seems to me that, by enacting section 63(2), the legislature has effectively imposed a wide ranging and substantial sanction against a patentee whose patent has not been drafted to an acceptable standard.

Partially valid patents: the cases before 1999

53. I turn to consider the effect of the authorities on this issue. There is no doubt that the courts have for a long time recognised the difference between a deleting amendment and a validating amendment: the distinction was discussed more than 35 years ago in C. Van der Lely NV –v- Bamfords Limited [1964] RPC 54. In that case, which was concerned with earlier legislation, the Patents Act 1949, the Court of Appeal expressed some uncertainty as to the consequences to the patent of refusing a deleting amendment. However, more recent authority suggests that the valid claims in a partially invalid patent are enforceable even in the absence of an amendment deleting the valid part.
54. In Gerber Garment Technology Inc. –v- Lectra Systems Limited [1994] FSR 471 at 483, Aldous J said this:

“If it was the law in 1919 that a patent with an invalid claim was invalid until amended, then it is no longer the law. The Court has power to grant relief in respect of a partially valid patent without requiring amendment.”

He reached that decision based on his earlier decision in Hallen Co. –v- Brabantia (UK) Limited [1990] FSR 134 at 138, and on the reasoning of the Court of Appeal in C. Van der Lely [1964] RPC 54.

55. The same view was taken by Millett LJ when Gerber went to the Court of Appeal. At [1995] FSR 492 at 499, he said:

“[S]ection 63… has swept away the old rule that the presence of an invalid claim rendered the whole patent invalid. Instead, such a patent is now treated as “partially valid”, and provided that the specification for the patent was framed in good faith and with reasonable skill and knowledge, the Court may grant relief in respect of the valid claims found to have been infringed.”

56. More recently, in the Court of Appeal, Aldous LJ in Lubrizol Corp –v- Esso Petroleum Limited [1998] RPC 727 at 790 in a passage at lines 6 to 17 referred to cases where “a Court has held that a patent is partially invalid and partially valid”. He continued:

“In such a case it can grant relief without requiring amendment or may direct that it be amended to its satisfaction. Thus, if a claim specifies more than one invention, it may grant relief in respect of one of those inventions even though the other invention is invalid.”

57. These observations therefore suggest that, in the case of a partially valid patent, the valid claims are enforceable even in the absence of a deleting amendment, i.e. an amendment deleting the invalid claims. If that is right, then it seems to me that it would be little short of absurd to refuse a deleting amendment, save (perhaps) in the most exceptional circumstances. In any particular case, the patentee and any alleged infringer of the valid claims are in no better and no worse position whether the deleting amendment is granted or not, and the public is clearly better off with the deleting amendment, because it is more desirable that invalid claims should not remain on the record. It also appears to me that, if the claims of a partially valid patent are enforceable and valid even in the absence of a deletion, it would be inconsistent to conclude that the refusal of an amendment to delete the invalid claims would lead to revocation of the patent. If that were the law, then no proprietor of a partially valid patent would apply for a deleting amendment, if he was in his right mind. Quite apart from anything else, that would scarcely be in the public interest, although, as mentioned above, the court, of its own motion, can require the patentee to amend.
58. There is one case which can be said to suggest that, even in the case of a partially valid patent, a refusal by the court to grant a deleting amendment will lead to revocation. I have in mind what was said by Aldous J in Chiron Corporation –v- Organon Teknika Ltd (No. 7) [1994] FSR 458 at 460:

“The defendants submitted that this is a case where the Court should not exercise its discretion so as to allow the amendment. Counsel did not shrink from the conclusion that he said resulted, namely that the patent should be revoked, thereby depriving the plaintiffs of any patent protection for the invention that I held had been made.”

59. That passage appears merely to record as submission what was said in the second sentence, without actually accepting its correctness. However, what Aldous J said immediately after that passage provides a degree of support for the view that he accepted the submission; he said:

“Clearly such a finding would be harsh and would only seem to provide justice if there are very exceptional circumstances.”

Further, in a subsequent passage in the judgment at [1994] FSR 463 Aldous J said this:

“In cases of deletion, a patentee will not be deprived of the fruits of his invention unless there are very compelling reasons to do so.”

60. However, it may well be that the contrary view was not argued, or that Aldous J was content to proceed on the assumption that the submission was correct, on the basis that it was a favourable assumption to the Opponents (whose case he ultimately rejected) because, if the valid parts of the patent had been enforceable even if the invalid parts had not been deleted, there would simply have been no reason not to delete the invalid parts.
61. Before turning to recent authority, it appears to me that the balance of the authorities so far considered plainly favours the conclusion that the valid claims of a partially invalid patent are enforceable irrespective of whether or not the patent is amended. From that, at least as I see it, it should follow that, save in perhaps the most exceptional circumstances, the court should grant a deleting amendment virtually as a matter of course, once it has held that certain claims of the patent are valid. However, this conclusion has to be judged in light of more recent authority.

Partially valid patents: the law since 1999

62. Kimberley-Clark Worldwide Inc. –v- Procter & Gamble Limited [2000] RPC 422 was relied on by HMR. It was a case concerned with a validating amendment. Laddie J held that, contrary to previous practice, the court should, almost as a matter of course, grant a validating amendment, in light of the practice of the European Patent Office in relation to European patents generally. The Court of Appeal disagreed. In his judgment, Aldous LJ referred to his judgment at first instance in SmithKline & French Laboratories Limited –v- Evans Medical Limited [1989] FSR 561 at 569, where he had said this:

“The discretion as to whether or not to allow amendment is a wide one and the cases illustrate some principles which are applicable to the present case. First, the onus to establish that amendment should be allowed is upon the patentee and full disclosure must be made of all relevant matters. If there is a failure to disclose all the relevant matters, amendment will be refused. Secondly, amendment will be allowed provided the amendments are permitted under the Act and no circumstances arise which would lead the court to refuse the amendment. Thirdly, it is in the public interest that amendment is sought promptly. Thus, in cases where a patentee delays for an unreasonable period before seeking amendment, it will not be allowed unless the patentee shows reasonable grounds for his delay. Such includes cases where a patentee believed that amendment was not necessary and had reasonable grounds for that belief. Fourthly, a patentee who seeks to obtain an unfair advantage from a patent, which he knows or should have known should be amended, will not be allowed to amend. Such a case is where a patentee threatens an infringer with his unamended patent after he knows or should have known of the need to amend. Fifthly, the court is concerned with the conduct of the patentee and not with the merit of the invention.”

As he pointed out, that passage was accepted by the Court of Appeal in Hsiungs’ Patent [1992] RPC 497.

63. There is no doubt in my mind that, so far as validating amendments are concerned, the reasoning and decision in Kimberley-Clark [2000] RPC 422 establishes that the 1977 Act gives the court a genuine discretion whether or not to grant such amendments, and its effect is that, if it refuses to do so, then the court should revoke the patent. It also appears to me that there is force in the point that the reasoning of Aldous LJ in Kimberley Clark [2000] RPC 422 is to the effect that the existence of the discretion whether or not to grant permission to amend, and the general approach to such discretion, applies equally to deleting amendments. However, any observations that the Court of Appeal in a case relating to validating amendments, even from a source as authoritative as Aldous LJ, have to be read in the context of the particular case. In addition, one must of course distinguish between those parts of his reasoning which are plainly ratio decidendi and those which are strictly obiter. If, as I believe to be the case, there are good grounds, in light of principle, authority (going back to Van der Lely in 1964), Statute (section 63), and Treaty obligations (the EPC), to distinguish between validating amendments and deleting amendments, then it seems to me that a decision and reasoning of the Court of Appeal in relation to a case involving validating amendments can properly be treated, where appropriate, as strictly obiter so far as deleting amendments are concerned. I express that view in a qualified way, because, in so far as the reasoning in the Court of Appeal in relation to validating amendments clearly applies equally to deleting amendments, it would not be right for me to depart from it. However, in my judgment, there is nothing in the reasoning in Kimberley Clark [2000] RPC 422 which requires me to depart from the conclusion I have reached on the basis of the Statutory and EPC material and the earlier cases. I reach that conclusion not only on the basis of consideration of the judgment in Kimberley Clark [2000] RPC 422 itself, but also, indeed more, on the basis of subsequent authority.
64. While there are passages in the judgment of the Court of Appeal in Kimberley Clark [2000] RPC 422, which may indicate that the court has a discretion whether or not to grant deleting amendments as well as validating amendments, the point seems to me to have been more specifically focussed on in Oxford Gene Technology Limited –v- Affymetrix Inc. (No. 2) [2001] RPC 310. That was another decision of the Court of Appeal concerned with validating amendments rather than deleting amendments. In his judgment, Aldous LJ said at [2001] RPC 320 that “Article 138(2) essentially corresponds to section 63(1) of the 1977 Act…”. He then turned to the argument that “to give effect to Article 138(2), the court has to exercise its jurisdiction under section 75 so as to permit the amendments, if they would have the result that [the] patent would be valid”. That argument was rejected in that case (which related to validating amendments) on the basis that:

“Section 63 is concerned with a case where the patent is partly valid as is Article 138(2); whereas section 75 permits amendment to validate an invalid patent. That difference was exposed in Van der Lely N.V. –v- Banfords Limited [1964] RPC 54” (paragraph 36).

65. Later on the same page, [2001] RPC 321, and, to my mind crucially for the purpose of the issue before me, Aldous LJ continued in these terms at paragraph 39:

“We did not hear argument on the amendments sought by OGT, but on their face they appear to be of the kind designed to validate an invalid patent rather than to limit the patent to a part which is valid. Thus it would seem that the court would have to exercise its discretion under section 75 when considering the amendments. If the amendments had been of the kind which reflected the fact that one claim was valid, then section 63 could apply provided that the claim was infringed. In those circumstances the word “may” in section 63 might be construed in a permissive sense to give effect to the word “shall” in Article 138(2).”

The contention that the Court of Appeal took the view that, by enacting section 63, the legislature gave effect to the first sentence of Article 138(2) is reinforced by the apparent equating of the two provisions in paragraph 41 of the judgment at [2001] RPC 322.

66. Unlike Oxford Gene [2001] RPC 310, and indeed unlike Kimberley Clark [2000] RPC 422, the present case is indeed of a kind which falls within the penultimate sentence of the passage I have quoted from in paragraph 39 of Aldous LJ’s judgment in Oxford Gene at [2001] RPC 321. It appears to me that, in those circumstances, the last sentence of that passage suggests, to put it at its lowest, that it might well be the case (i.e. that there is no authority which precludes the conclusion) that, in order to give effect to the first sentence of Article 138(2), the court should grant an amendment, because it is a deleting amendment and there are valid claims.

Partially valid patents: conclusion

67. Accordingly, I conclude that where an amendment is solely a deleting amendment, it should, save (possibly) in an exceptional case, be granted. It seems to me that that conclusion is (a) consistent with the United Kingdom’s Treaty obligations under Article 138(2), (b) consistent with the natural meaning and effect of section 63(1), (c) not inconsistent with the provisions of section 72 and section 75, (d) consistent with the well accepted distinction between deleting and validating amendments which goes back to Van der Lely [1964] RPC 54, (e) logically and commercially sensible in light of the law as laid down in Gerber [1994] FSR 471 and [1995] FSR 492, and (f) open to me in light of Oxford Gene [2001] RPC 310. Accordingly, I conclude that, where the amendment sought to be made to a patent is purely a deleting amendment, because there are claims which would be valid even in the absence of the invalidity which has been established and in the absence of the deletion, the court should grant the deleting amendment.

Discretion to allow or refuse amendment

68. Assuming (contrary to my view) that there is a power to refuse a deleting amendment, then it appears to me that the cases support the proposition that the court should be very slow to refuse a deleting amendment.
69. In this connection, I have already quoted the observations of Aldous J in Chiron (No. 7) at [1994] FSR 460. That approach seems to me to have been followed in subsequent cases. Thus, in Mabuchi Motor KK’s Patents [1996] RPC 387, Jacob J permitted an amendment involving the deletion of claims even though he had “no doubt that the patent was not framed with reasonable skill and knowledge” (see at [1996] RPC 402 lines 44 and 45) and even though he thought that the inventor in that case “never thought his invention was wider than that which is now claimed” (see at [1996] RPC 403 lines 11 to 12). The same view was taken by Pumfrey J in Nutrinova Nutrition Specialities & Food Ingredients Gmbh –v- Scanchem UK Limited (No. 2) [2001] FSR 831 at 837 when he referred to the need for “exceptional circumstances” before the Court would refuse permission to amend by way of deletion.
70. HMR contends that, even where a deleting amendment of a patent is sought, the five factors enunciated by Aldous in SmithKline at [1989] FSR 569, as subsequently approved by the Court of Appeal, and as quoted above, must be applied. In this connection, I should add that in Kimberley-Clark at [2000] RPC 422 at 438, Aldous LJ emphasised that the obligation to disclose “has been curtailed with the advent of active management of cases by the judges”. In Oxford Gene [2001] RPC 310 at 317, Aldous LJ stated that, while “the obligation of good faith requires the patentee to put forward correct reasons for the amendment”, there is “no obligation upon a patentee… to waive privilege in respect of any document” and that “the maintenance of privilege does not enable the Court to draw an adverse inference against the person who maintains his privilege”.
71. HMR contends that, on the basis that amendment is a matter of discretion, the five factors, now that they have been approved twice by the Court of Appeal, should be applied in a deleting amendment case. The five factors having not only been laid down and applied by this Court, but also approved by the Court of Appeal, have to be accorded great weight. However, I am reluctant to conclude, even in light of their impeccable pedigree, that they should be applied mechanically, at any rate in a case such as the present. First, assuming in HMR’s favour, that the power to grant an amendment is a matter of discretion, because of the word “may” in section 75(1) of the 1977 Act, then it seems to me inappropriate to treat that discretion as fettered by judge-made rules, although, of course, any rules which have been applied in this Court and approved by the Court of Appeal must at the very least be considered, and, indeed, must provide useful guidance. In this connection, the imposition of judge-made rules on the exercise of a Statutory or quasi-Statutory discretion was recently disapproved by the Court of Appeal in Denyse Audergon –v- La Baguette Ltd (23^rd January 2002, Times Law Report of 31^st January 2002).
72. Secondly, if, as the authorities indicate, the discretion should almost always be exercised in favour of granting a deleting amendment, then that first point is reinforced in this case. Thirdly, the extent to which the five factors are to be applied must depend upon the sort of considerations identified by Aldous LJ, namely active case management and maintenance of privilege. Fourthly, at least in my view, it must be inevitable that guidelines of this sort have to be applied with a degree of flexibility. For example, there may be a case where a patentee, who satisfies the other requirements, has failed to apply to amend within a reasonable time, but that this has caused no prejudice to anyone, or such prejudice that it has caused can easily be remedied by ordering the patentee to pay a relatively small amount of money. If refusal of the amendment would lead to a very valuable patent being revoked, then, at least in some circumstances, it would seem quite disproportionate that a patentee who had delayed unreasonably, possibly for a relatively short time, should be refused an amendment and therefore deprived of his patent, even though there was no other reason to criticise the patentee in relation to the amendment or otherwise.
73. That is not intended to detract from the salutary guidelines laid down by Aldous J in SmithKline at [1989] FSR 561 at 569. In relation to delay, for instance, even if my view is correct, a patentee who is aware that his patent requires amendment should not assume that (if the grant of an amendment is indeed a discretionary matter) the amendment will automatically be granted if the only criticism of his conduct is unreasonable delay. Each case will have to be judged on its own particular facts, and any patentee who delays does so at his own risk. Furthermore, even if the court concludes that it should grant the amendment (either as a matter of pure discretion or because its discretion is effectively trammelled) there appears to me to be no reason why permission to amend should not be subject to conditions in an appropriate case, and obviously where the patentee’s conduct is worthy of criticism, the court may feel that the criticism should be reflected in conditions.

Damages, expenses and costs: if section 63(2) does not apply

74. Section 63(1) gives the Court a discretion to grant relief against an infringer in a case where the patent is amended. However, where the patentee fails to establish that “the specification for the patent was framed in good faith and with reasonable skill and knowledge”, section 63(2) effectively prohibits the Court from granting relief “by way of damages, costs or expenses”, but there is nothing to take away the Court’s discretionary power to grant other relief (e.g. injunctive relief).
75. In my view, although the power to grant relief against an infringer of a valid claim in a patent which includes invalid claims is discretionary (assuming that the patent was framed in good faith and with reasonable skill and knowledge), the Court would normally grant such relief against an infringer in such a case unless satisfied that the infringer was in some way unfairly misled by the invalid claims of the patent. Further, it seems to me that the mere fact that a patent may have been drafted so as to include invalid claims should not, in the absence of special factors, prevent the patentee being entitled to the full range of relief against an infringer of one or more of the valid claims, provided it is a case where section 63(2) does not apply.
76. The view that the Court will normally accord relief under section 63(1) is supported by observations, at first instance and in the Court of Appeal. Thus, there is a statement by Aldous J in Hallen at [1990] FSR 134 at 149 to this effect:

“[It] is for a defendant to establish that special conditions exist before terms will be imposed or a patentee will be deprived of part of his damages. A patentee who has made an invention, disclosed it to the public in his specification and established that his specification was framed in good faith and with reasonable skill and knowledge is entitled to the full rewards provided by the law unless some special circumstances exist.”

77. Further, in Gerber at [1995] FSR 492 at 499, Millett LJ said, in relation to a case where the patent contained invalid claims as well as valid claims, and where the defendant had infringed a valid claim:

“[I]t will remain the fact that the defendant has infringed a valid claim, and that the plaintiff ought not to be deprived of his right to damages in respect thereof without good reason. If the presence of the invalid claims has induced the defendant to act as he did, then it would be unjust to order him to pay damages prior to the date on which the invalidity of the claims was established. If, on the other hand, the presence of the invalid claims has had no effect upon the defendants’ conduct, then ordinarily it would not be just to deprive the plaintiff of any part of his damages.”

Damages, costs and expenses: section 63(2)

78. As I have said, section 63(2) appears to be mandatory in its effect. It imposes the burden on a patentee, whose patent the court has found to be partially invalid, to establish that the patent was drafted in good faith and with reasonable skill and knowledge. If he does not do this, then, even if his patent remains (at least partially) valid (either because it is amended or because it does not need amendment) he cannot claim damages costs or expenses from an infringer. In this connection, the law was helpfully summarised by Aldous J in Chiron (No. 7) [1994] FSR 458 at 467 to 468. Quoting from his earlier decision at first instance in Hallen at [1990] FSR134 at 142, he said this:

“[I]t is my view that section 63(2) imposes upon a plaintiff a duty to prove on the balance of probabilities two things: first that the specification was framed in good faith. That requires a plaintiff to prove that the specification was framed honestly with a view to obtaining a monopoly to which, on the material known to him, he believed he was entitled. Secondly, that the specification was framed with reasonable skill and knowledge. The words “skill and knowledge” are a composite phrase relating to the competence employed in framing the specification and require the specification as framed to be in the form in which a person, with reasonable skill in drafting patent specifications and a knowledge of the law and practice relating thereto, would produce.”

79. Aldous J went on to explain that, in making those observations:

“I did not have in mind the possibility that the draftsman may not have been properly instructed on the details of the invention. In such a case, a patentee cannot be in a better position than the patentee who properly instructs the draftsman.”

80. A question which does not seem to have been considered in any of the cases to which I have been referred, is the tension between the inevitable concentration of the parties and the Court on the skill and knowledge involved in the drafting of a specific passage in the patent, and the skill and knowledge employed in the drafting of the patent as a whole. In this case, as in I suspect virtually every case involving a dispute as to the applicability of section 63(2), the evidence and argument have focused on the drafting of specific passages in the Patent, namely three paragraphs of Example 10 and the closing part of Claim 19. Accordingly, the questions on which the contentions have tended to concentrate is whether those parts of the Patent were framed in good faith and with reasonable skill and knowledge.
81. HMR’s contention is that the requirement in section 63(2) that “the specification” be drafted to the appropriate standard means that each and every part of the specification must be drafted to the appropriate standard, and, therefore, if the patentee fails to establish that each and every part of the specification has been drafted to the requisite standard, no damages, costs or expenses for any infringement of a patent can be granted. Amgen’s argument is that, before section 63(2) can deprive the patentee of any damages, costs or expenses for infringement, the court must be satisfied (a) that, in light of the parts of the specification which are inaccurate, and in light of the parts of the specification which are satisfactory, that the specification viewed as a whole was not drafted to the requisite standard, and (b) that there is some sort of nexus between the parts of the specification which have been found to be invalid and whose drafting has fallen below the requisite standard, and the infringement which has been established, or would otherwise have been established.
82. On the one hand, as a matter of ordinary language, what appears to be required by Section 63(2) is a consideration of the skill and honesty devoted to the drafting of the whole of the specification, and not merely to a specific sentence or passage in the specification. In this connection, it is not very difficult to conceive a case where, for instance, a very long and detailed specification with many aspects and features can fairly be said, viewed as a whole, to have been drafted “with reasonable skill and knowledge” even though a couple of sentences, or even paragraphs, could be said to have fallen short of that standard.
83. On the other hand, it can be said with force that it cannot have been the intention of the 1977 Act that, particularly in a case involving a long and complex patent, the parties or the Court should have to go through all the contents of the patent in order to check whether, taking into account the contents of every line, the specification as a whole was drafted with reasonable skill and care. Yet, on the literal reading of section 63(2), it could be said that such a pedantic approach to a patent is effectively required.
84. In my view, the correct approach, which appears to me to be consistent with the wording of section 63(2) and not inconsistent with the cases to which I have been referred, is as follows. One must inevitably initially concentrate or focus on the passages in the specification which are said to be inaccurate, and ask oneself whether they were framed in good faith and with reasonable skill and knowledge. If so, then the patentee has no problem under section 63(2). If they were not so framed, then the Court must ask itself whether, bearing in mind its conclusions as to the inadequacies of the patentee and its advisers in the drafting of the passages in question, the specification was “framed in good faith and with reasonable skill and knowledge”.
85. In considering that issue, the importance of the specific passages which have been found to be inaccurate and in respect of which the patentee has fallen below the requisite standard is obviously a very important factor. Similarly, the degree to which the patentee and his advisers have fallen below the requisite standard of good faith, skill and/or knowledge in drafting the specific passage or passages may well affect the determination of whether or not the specification was drafted to the appropriate standard. A relatively small failure, which nonetheless represents a lack of reasonable skill, in relation to a minor passage in the specification, may well not be enough to prevent the patentee from establishing that the specification was drafted with reasonable skill. On the other hand, flagrant dishonesty in drafting an important passage in the specification may inevitably lead the court to conclude that the specification was not drafted in good faith. It must be a question of fact and degree in each case. I appreciate that this approach is less clear cut than that advanced by HMR, but it does seem to me to be more in accordance with the Statutory wording. It also appears to me that there is a strong case for saying that, while the court should certainly not be indulgent to the drafting of patents, it is not right that every time a patent manifests a single failure of skill or knowledge, section 63(2) is engaged.
86. However, I reject Amgen’s case that there must be a nexus between the error and the infringement before section 63(2) can apply. First, it would involve implying a significant restriction into the sub-section, and this is something the court should not be prepared to do unless there is a compelling reason: no such reason has been made out. Secondly, it would involve an implication of a rather imprecise nature, which in some cases might be difficult to apply. In the present case, for instance, there could be said to be a nexus because HMR was alleged to infringe Claim 19, but there could equally be said to be no nexus, because I concluded that HMR infringe even if Claims 19 to 25 are excised. Thirdly, particularly if I am right about the effective absence of discretion in the case of a deleting amendment, the notion that section 63(2) represents a widely applicable sanction against a patentee who has drafted the specification ineptly or worse, appears to have real justification.

Section 62(3)

87. For completeness, I should mention that, in support of its case that Amgen should not be entitled to recover damages, expenses and costs, HMR, in addition to section 63(2), also relies on section 62(3). This provides:

“Where an amendment of the specification… has been allowed under any of the provisions of this Act, no damages shall be awarded in proceedings for an infringement of the patent committed before the decision to allow the amendment unless the Court… is satisfied that the specifications of the patent as published was framed in good faith and with reasonable skill and knowledge.”

88. HMR’s argument, in so far as it relies on section 62(3), essentially fastens on the second paragraph of Example 10, whose deletion before the Appeal Board represented an amendment which was allowed in the past, and therefore could be said to fall within section 62(3). HMR contends that the second paragraph of Example 10 was not “framed in good faith” or alternatively was not “framed… with reasonable skill and knowledge”, and therefore, even if its argument in relation to the first paragraph of Example 10 based on section 63(2) fails, Amgen should nonetheless not be entitled to recover any damages from HMR until the decision of the Appeal Boards to allow the deletion of the second paragraph.
89. It does not appear to me that the issues on section 62(3) involve any points of principle which have not already been discussed in relation to section 63(2). Furthermore, given that I am considering the drafting of the second paragraph of Example 10 as error (c) under section 63(2), it does not seem to me that it is helpful to consider as a separate matter the question of Amgen’s entitlement to relief in light of section 62(3).

THE ISSUES OF FACT AND INFERENCE

Introductory

90. The evidence and the arguments have centred on the knowledge and state of mind of Amgen and their advisers, and in particular their US patent agent, Mr Michael Borun, (a) at the time of the making of the fourth US Patent application around the end of November 1984, and (b) at the time of the first hearing before the Appeal Board in September 1994. November 1984 was the time when the three paragraphs were inserted for the first time into Example 10, namely on the filing of the fourth US Patent application, and they were required at that time to support the Claim which ultimately became Claim 19 of the Patent. It was this application which was the basis for the European Patent application, which was filed less than two weeks later. The reason for concentrating on Mr Borun is that it was his firm, now Marshal Gerstein & Borun, and he in particular, who took instructions from Amgen, and who ultimately drafted the US Patent applications.
91. The reason for concentrating on the hearing before the Appeal Board in September 1994 is that it was at that stage that the contents of the first paragraph assumed particular importance. Between 1984 and 1988 nothing of great relevance occurred in relation to the Patent; between 1988 and 1994, the European Patent Office, through the Examining Division and Opposition Division, was content with a formulation of the relevant Claim which did not depend on the three paragraphs. However, at least according to HMR, it was the contents of the three paragraphs of Example 10 which enabled Amgen to retain Claim 19, albeit in an amended form, because, without the new limitation proposed in Auxiliary Request 11, the Appeal Board would not have upheld Claim 19, and that limitation was only justified by the contents of the first paragraph of Example 10. Again, Mr Borun is said by HMR to have been the centrally relevant individual, not only because he was present on behalf of Amgen at the hearing before the Appeal Board and had originally drafted the Patent, and in particular the three paragraphs, but also because, having acted for Amgen in the proceedings before the USPTO, the Chugai litigation, and the interference proceedings, he had obtained further highly relevant information.
92. In addition to the relevant documents, oral evidence was given by witnesses on behalf of Amgen. HMR elected to call no evidence. I heard from Mr Borun, Amgen’s US patent attorney, and from Mr John Brown, the relevant partner in Amgen’s European patent agents. In addition, I heard evidence from Mr Steven Odre, senior vice president and general counsel of Amgen, who had the in-house supervisory responsibility for the prosecution of the US and European patent applications. I also heard from Dr Thomas Strickland who had carried out experiments on behalf of Amgen, and gave evidence to the Appeal Board. Finally, I heard evidence from Mr David Bannerman, a partner, and since 1997 chairman, of patent agents, Withers & Rogers. He was called as an independent expert.
93. The most convenient way of dealing with the questions of whether any of the three errors involved a lack of reasonable skill and knowledge and/or a want of good faith, appears to me to be as follows. I shall first deal with whether error (a) involved at least a want of reasonable skill and care in 1984. I shall then turn to deal with the same issue as at 1994 in relation to error (a). I shall then turn to error (b), which involves traversing much of the same ground. I shall then deal with error (c). Finally I shall deal with the question of whether any of the errors involved want of good faith.

Error (a) in 1984

94. Error (a) is in the first paragraph of Example 10, and involves concentrating on the information about the apparent molecular weights on SDS-PAGE of COS rEPO and urinary EPO. It seems clear that the person who had carried out the relevant experiments at Amgen was a member of Dr Lin’s team, Dr Joan Egrie, during 1984. Dr Egrie kept notebooks in which she contemporaneously recorded the results of experiments she carried out, including the relevant experiments in this connection.
95. At some point before he drafted the fourth US Patent application, it seems pretty clear that Mr Borun had a discussion with Dr Egrie about her work relating to the performance of various types of EPO’s on SDS-PAGE, as a result of which she agreed to send him copies of relevant pages of her notebook. That is supported by a number of factors. First, Mr Borun had made up a file called “The Egrie input file” (which I shall call “the File”) in his office, containing photocopies of pages from Dr Egrie’s notebooks, and that seems to suggest that he asked her for them. Further, the first page of the File is a note dated 31^st October 1984 (one month before the filing of the fourth US Patent application) in the handwriting of Mr Borun’s assistant, referring to the fact that certain documents had been “requested by MFB” (i.e. Mr Borun). Thirdly, the second page of the File is a note from Dr Egrie to Mr Borun and his assistant stating that she “thought that the simplest thing to do was to xerox the relevant expts. for you out of our notebooks”. Fourthly, in her deposition in the US infringement proceedings, Dr Egrie said that she thought that that is what happened. Further, while I did not find Mr Borun a satisfactory witness, the conclusion appears to be consistent with his evidence.
96. The File contained some rather indistinct photocopies of the results of SDS-PAGE experiments, detailed notes explaining and analysing the experiments, and some conclusions. In order to understand Dr Egrie’s experiments and notes, it must be understood that she had three sources of urinary EPO. The first was supplied to her by Dr Eugene Goldwasser (“Goldwasser uEPO”); the second was known as Lot 82 (“Lot 82 uEPO”); the third was known as Alpha Therapeutics (“Therapeutics uEPO”).
97. In one experiment, Dr Egrie recorded that CHO rEPO and Lot 82 uEPO had the “same size, although CHO is very heterogeneous”, that “Goldwasser uEPO had a lower molecular weight than Lot 82” uEPO, and that “Therapeutics uEPO is… same size as CHO + Lot 82”. Dr Egrie recorded the result of a second experiment showed that Goldwasser uEPO and Lot 82 uEPO again had an apparent “MW difference”. In relation to COS rEPO, she expressed the conclusion that:

“Recombinant monkey and human EPO produced by COS cells have the same molecular weight as native urinary EPO [Goldwasser’s [urinary] EPO]. This result indicates that the recombinant EPO is glycosylated to the same extent as the native protein.”

98. In further conclusions, she stated that “size of Gene’s standard [i.e. Goldwasser urinary EPO] ~ = size of COS cell produced EPO as was seen in the prior section IV” and that “size of CHO-cell material is larger than COS or Gene’s standard” and that “CH is ~ to Lot 82 EPO”.
99. On any fair reading of the File, it seems to me that, at least in Dr Egrie’s view, the position was tolerably clear and was as follows. If one confined oneself to comparing recombinant EPOs with Goldwasser uEPO, CHO rEPO had a somewhat higher molecular weight than urinary EPO, but COS rEPO had the same apparent molecular weight as urinary EPO. On the other hand, once one extended the comparison to two other urinary EPOs, namely Lot 82 uEPO and Therapeutics uEPO, CHO rEPO had the same apparent molecular weight as those two urinary EPOs.
100. Amgen can point to a small degree of latitude in the views expressed by Dr Egrie in the File, in the sense that she has indicated that different EPOs performed approximately the same, and that some EPOs were more heterogeneous than others. However, it does not appear to me that there is much room for disputing the above summary of her conclusions as recorded in her notebooks, and indeed in the File, in 1984. Further, the notion that she formed the views I have described is consistent with subsequent evidence of her views, to which I will shortly turn.
101. On the basis of the File, and in particular Dr Egrie’s views as expressed therein, it appears clear that:

(1) If one confines oneself to Goldwasser uEPO, then:

(a) the statement in Example 10 that COS rEPO had a “slightly larger” apparent molecular weight than pooled urinary EPO is incorrect: they ran the same on SDS-PAGE;

(b) the statement that CHO rEPO had a higher apparent molecular weight than urinary EPO is correct.

(2) If one includes Lot 82 uEPO and/or Therapeutics uEPO, then:

(a) the statement about the performance of COS rEPO remains inaccurate;

(b) the statement about CHO rEPO is no longer reliable, because it has the same apparent molecular weight as some urinary EPOs.

102. Mr Borun said in his evidence that, although he had plainly received the File, he does not believe that he read it before he prepared the fourth US Patent application. I do not accept that evidence. First, it seems to me inherently unlikely that he did not read documents, for which he had specifically asked, as I find he did. Secondly, I consider it is very likely that Mr Borun would have appreciated that the File was, to put it at its lowest, likely to be of interest on one of the main aspects of the Patent application which he was then concerned with drafting, namely the last three paragraphs of Example 10 in the fourth Patent application (which was submitted some four weeks after he received the File). Thirdly, Mr Borun said that (not surprisingly) it was his practice to read documents sent to him by a client in relation to a patent which he was drafting. Fourthly, there is no suggestion of his having received any other documents relating to experiments carried out by or on behalf of Amgen in relation to the performance of the various EPOs on SDS-PAGE, a topic specifically dealt with in the first paragraph he was drafting around this very time. Fifthly, the information contained in the File was of particular potential importance, because Mr Borun wanted to be able to persuade the USPTO that there was an identifiable distinction between rEPOs made in accordance with the teaching of the Patent, and prior art urinary EPO.
103. So far as Mr Borun’s denial that he read the File in 1984 is concerned, I am unconvinced by it. He did not strike me as a reliable witness. He tried to avoid answering questions which presented him with difficulties. He was argumentative. He put forward explanations which were inconsistent with evidence given in earlier proceedings (and in particular the US infringement proceedings). He tried to avoid answering questions about error (a) by seeking to deflect attention to the latter part of the first paragraph. He mentioned for the first time facts which one would have expected him to raise earlier, particularly bearing in mind his close connection with the case and his knowledge of the legal issues. Further, on more than one occasion, Mr Borun suggested that Dr Egrie “would agree” with the contents of the first paragraph of Example 10. Not only does that seem to me very hard to accept in light of his acceptance that the contents of the File are inconsistent with some parts of that paragraph, but it is also hard to reconcile with the fact that he also accepted that Dr Egrie would have been unlikely to depart from the views expressed in her notebooks.
104. In connection with the File, Mr Borun suggested that he must have had another source of information because otherwise he could not have known the designation “E.C.3.2.1” which was inserted in the first paragraph. He mentioned this point of his own initiative more than once, without being asked about it in cross examination. Further in his deposition in the US infringement proceedings he had said that he thought that he may well have looked up the designation himself. I accept that, particularly in connection with matters which occurred a long time ago, memory can fade, and indeed can be inconsistent at different times. However, I got the firm impression that Mr Borun did not really have any significant recollection whether he had looked at the File before he drafted the fourth US Patent application, but, because he appreciated the obvious difficulty in reconciling the contents of the File with some of the contents of the first paragraph of Example 10, he sought to persuade the court (and indeed may have persuaded himself) that he cannot have read the File in 1984. Indeed, I note that, in his deposition in the US infringement proceedings, Mr Borun said that he could not say whether or not he had read the File.
105. To an extent, I suppose that it can be said to be to Mr Borun’s credit, he conceded that there were at least parts of the File which were inconsistent with what he had written in the first paragraph of Example 10, although that was probably an inevitable concession. He also said that, had he read the File, he would have asked questions of Dr Egrie, in particular about the suggestion that rEPOs appeared to have the same apparent molecular weight as some urinary EPOs.
106. There is no indication in any documentation or in any oral evidence (whether given in these proceedings or in any of the other proceedings to which I have referred) which even suggests that anyone from Amgen (or indeed anyone else) gave any information or opinion in 1984 to Mr Borun which was inconsistent with that of Dr Egrie as contained in the Files. Mr Borun suggested that Dr Lin may have told him something relevant in this connection, but, while I am satisfied that he had discussions with Dr Lin, there is nothing to suggest that he would have expressed a view, let alone did express a view, inconsistent with that of Dr Egrie as recorded in her notebooks. Again, to his credit, Mr Borun accepted that it was unlikely that Dr Lin would have said anything inconsistent with the contents of the File.
107. It is fair to say that the very fact that some of the contents of the first paragraph are inconsistent with the contents of the File could be said to give some support to the view that Mr Borun did not read it. However, the fact that the only written evidence apparently made available to Mr Borun in relation to SDS-PAGE experiments does not support all that he wrote into Example 10 in November 1994 is, in my judgment, insufficient to establish that he did not read that information. Part of what he wrote in relation to the SDS-PAGE experiments was, at the very least, arguably consistent with what was in the File, namely that the CHO rEPO displayed a higher apparent molecular weight than some urinary EPO. Apart from the possibility of his having talked to Dr Lin or Dr Egrie, there is simply no evidence of any conversation or any document from which he could have got information about SDS-PAGE. Given that, as Mr Borun accepted, it is unlikely that Dr Egrie, or indeed Dr Lin, would have said anything different from what was in the File, that point takes matters little further anyway. Accordingly, the fact that the contents of the File are not reflected in at least part of the description of the SDS-PAGE experiments in the first paragraph is quite insufficient to persuade me that Mr Borun did not look at the File, in light of the other factors to which I have referred.
108. It may not matter whether Mr Borun read the File around the time he received it and, in particular, before he filed the fourth US Patent application. If, as I think, he did read it, then, as he effectively accepted in evidence, he could not justifiably have written what he wrote in the first paragraph of Example 10 about COS rEPO, without at least talking to Dr Egrie about the contents of her notebooks, which I am satisfied he did not do. In that connection, in her deposition in the United States proceedings between HMR and Amgen, Dr Egrie did not recollect Mr Borun having had a further conversation with her. Indeed, in his evidence Mr Borun has never suggested that he had a further conversation with Dr Egrie after receiving the File, and there is no suggestion of such a further conversation in any of the documents. There is no explanation as to why Mr Borun did not make such enquiries, and, in my judgment, he should have done so. If he did not look at the File, then it seems to me clear that he failed to do something which he ought to have done, and, had he done so, then, again as he accepts, it would have been appropriate for him to have talked to Dr Egrie before he could properly have drafted the first paragraph of Example 10 as he did.
109. Of course, I am not ultimately concerned with whether or not Mr Borun himself fell below the standard one expects of a patent agent in this connection. I am concerned with the question of whether, bearing in mind the information available to Amgen and its advisers, the first paragraph of Example 10 was drafted to the requisite standard. Strictly, I am not considering the drafting of the fourth US Patent application of 30^th November 1984, but the drafting of the European Patent application filed some 12 days later. The latter point appears to me to involve a distinction without a difference: as I have mentioned, the fourth US Patent application was effectively the same document as the first European Patent application. I have reached the conclusion that, in relation to the performance of COS rEPO relative to urinary EPO in SDS-PAGE experiments, Example 10 was not drafted with reasonable skill and knowledge. Whether one looks at the matter from the point of view of Mr Borun or Amgen, the only experiments, records and expert views which appear to have existed were those contained in the File, and they showed a clear record of COS rEPO having the same apparent molecular weight as the urinary EPO upon which Amgen effectively rely, namely Goldwasser uEPO.

Error (a): 1994

110. HMR points out that there were a number of different documents and other pieces of evidence which came to the attention of Mr Borun between 1984 and 1994 and, in particular which Mr Borun read during the course of the interference proceedings and the Chugai litigation, in which he was involved on behalf of Amgen. That would mean that he would have perused those documents by 1991. HMR says that this evidence at least should have led him to appreciate that Amgen’s own experts on the topic, and in particular Dr Egrie, continued to take, and consistently took, the view that COS rEPO manufactured in accordance with the teaching of the Patent, manifested the same, or approximately the same, apparent molecular weight on SDS-PAGE as urinary EPO.
111. First, there are Dr Egrie’s notebooks, which would have included all the pages in the File, which Mr Borun accepted he would have read in relation to the interference proceedings and the Chugai litigation. Secondly, Mr Borun accepted that he would have paid careful attention to Dr Egrie’s deposition and declaration of 18^th March 1991 in the interference proceedings, in which she said that “the carbohydrate portion” of COS rEPO and of pooled urinary EPO “were of approximately the same size”, and that urinary and recombinant EPOs “migrate identically” and “co-migrate”. There was nothing else in the evidence to suggest that this conclusion was wrong, either in Amgen’s view or at all.
112. Thirdly, Mr Borun saw three publications in respected peer-reviewed journals in 1985 and 1986, where most of the authors were current or previous Amgen employees, which included at least one photograph of an SDS-PAGE gel showing, and reported as showing, that COS rEPO migrated effectively identically to urinary EPO, and therefore displayed the same apparent molecular weight. Thus, in one of those papers, in Immunobiology, Vol 172, page 213, of which Dr Egrie was the lead author, it was stated in the abstract that:

“By Western analysis, the recombinant and human urinary EPO migrate identically.”

In the highly respected New England Journal of Medicine (Vol 316, page 73) in a paper of which Dr Egrie was also one of the authors, there was this:

“In addition, the carbohydrate portion… of the natural urinary and recombinant hormones are indistinguishable…”

That meant that the two types of EPO must have the same apparent molecular weight, because, virtually by definition, the polypeptide backbone of the two EPOs was the same, and Mr Borun would or should have understood this. In her evidence in the Interference Proceedings, Dr Egrie specifically confirmed that she stood by her views in these papers.

113. Fourthly, in the interference proceedings, a brief was submitted before US Board of Patent Appeals and Interferences, on behalf of Dr Lin, who, as I have mentioned, was being backed by Amgen, and one of the three counsel named on it was Mr Borun. On page 18 of the brief, under the main heading “Statement of the Facts”, and the sub-headings “The Interference History” and “Dr Joan Egrie”, there was this:

“Dr Egrie… found that COS cell-expressed recombinant EPO and the pooled human urinary EPO migrated identically on SDS-PAGE, while CHO cell-expressed recombinant EPO moved differently…”

114. Fifthly, as I have mentioned, Amgen had been applying for FDA approval for the marketing of recombinant EPO. In their IND, they had stated unequivocally that recombinant EPO and naturally occurring urinary EPO “co-migrated” i.e. displayed the same apparent molecular weight by SDS-PAGE. Mr Borun said that he may not have seen that document, and, although he did not impress me as a witness, I accept that he may not have done so. However, Mr Borun did see the PLA, which, while not referring expressly to SDS-PAGE experiments, did indicate that all the tests carried out by and on behalf of Amgen suggested that recombinant EPO was “identical within the error of the methods” to urinary EPO.
115. There do not appear to have been other experiments, or other scientists’ views of experiments, which existed, let alone which were communicated to Mr Borun, prior to the hearing before the Appeal Board, which would or even could have suggested to him that COS rEPO manifested a higher apparent molecular weight by SDS-PAGE than any urinary EPO. In other words, by 1994, there was considerably more evidence available to Mr Borun in connection with the SDS-PAGE experiments, than was available to him than in 1984. In all these circumstances, subject to any factors pointing the other way, in my judgment, he, and therefore, effectively through him, Amgen, fell below the requisite standard of skill and knowledge when they supported the first paragraph of Example 10 in its entirety, and in particular error (a), and therefore Auxiliary Request 11. It seems to me that, apart from error (a) itself, there was nothing to support the statement in the first paragraph of Example 10 so far as it related to the performance of COS rEPO against urinary EPO on SDS-PAGE, either by way of experiments or by way of any scientists views of experiments.
116. It is suggested by Mr Waugh that there may have been some sort of change of mind on the part of Amgen as to the performance of COS rEPO as against urinary EPO on SDS-PAGE during the 10 years between 1984 and 1994. I cannot accept that. First, there is nothing to support it by way of oral evidence. I appreciate that neither Dr Egrie nor Dr Lin, who do not work any longer for Amgen, have been prepared to come and give evidence, but there is no indication in any document or in their evidence, depositions or declarations in other proceedings to suggest that either of them, or that any other relevant scientist, had changed his or her views, as to the effect of any SDS-PAGE experiment relating to COS rEPO and urinary EPO. Secondly, apart from the contents of Example 10 of the Patent, as drafted by Mr Borun in or before November 1984, there is nothing to suggest that the relevant scientists at Amgen, and in particular Dr Egrie, had ever taken a view different from that which was consistently held in Dr Egrie’s notebooks, in Dr Egrie’s depositions, and in the papers published by Amgen scientists, including Dr Egrie. To my mind, the simple and obvious answer is the correct one: error (a) was indeed an error, and it was perpetrated by Mr Borun at the end of 1984, and has been maintained (and where necessary relied on) by and on behalf of Amgen ever since.
117. It is further argued by Amgen that error (a) was not, even viewed on its own, due to want of skill or knowledge on the part of Amgen and its representatives, in September 1994. I accept that one must be careful before characterising an error as being attributable to want of reasonable skill and knowledge. The mere fact that an error finds its way into a patent may be due to a misjudgment or an unfortunate oversight which cannot be characterised as want of reasonable skill, just as much as not every mistake by a professional person constitutes negligence. Further, I accept that one must be careful of relying on wisdom of hindsight. This was a long and complicated patent with many factors and features, and it would, I accept, be wholly unrealistic to expect Amgen and its advisors, even taking into account the very large team who attended the Appeal Board on their behalf in September 1994, to remember every relevant fact and document which had been in their possession, or which they had seen. Nonetheless, I do not consider that this sort of consideration can exonerate Amgen from a finding of lack of reasonable skill and knowledge in relation to error (a) in September 1994.
118. First, the importance of the first paragraph of Example 10 to the protein claims of the Patent must have been apparent to Amgen, and in particular to Mr Borun, and similarly the importance of the protein claims (i.e. what are now Claims 19 to 26) themselves. Mr Borun himself said that the protein claims of the Patent were important, and it is self-evident that they were, particularly in light of the uncertainty (which even now still exist, possibly to a more limited extent) as to the validity of claims to DNA sequences. The contents of the three paragraphs were needed to justify the predecessor of Claim 19 in the original Patent application in 1984. Mr Borun and other representatives of Amgen must have appreciated during the hearing before the Appeal Board in November 1994, the vital importance to Amgen of being able to distinguish recombinant EPOs made according to the teaching of the Patent from prior art EPOs, i.e. from urinary EPO. Without such a distinction, they would have realised that the protein claims might not be approved by the Appeal Board, essentially because of lack of novelty.
119. Indeed, it goes further than this. It is clear that, at the hearing before the Appeal Board, attention was concentrated on the first paragraph of Example 10, both in the evidence and by reference to the terms in which what is now Claim 19 was proposed to be amended. Indeed, attention had already been focused on the first paragraph of Example 10 when the matter was considered by the Opposition Division, not least because of its potential relevance to Claim 19. Additionally, the Opponents had produced expert evidence, and in particular that of a Dr Conradt, which bore directly on this issue. I note that the Appeal Board concluded that the only evidence available to support the contention that COS rEPO displayed a slightly higher molecular weight was Example 10 itself, i.e. error (a). It seems to me that, particularly bearing in mind the duty of a patentee to be candid on this sort of issue with the European Patent Office, and the fact that the issue was one of the items in the forefront of the dispute before the Appeal Board, it does not involve wisdom of hindsight to conclude that there was a want of skill and care on the part of Amgen and its advisers when supporting the first paragraph of Example 10, and in particular the contents of error (a), in front of the Appeal Board.
120. It is also contended on their behalf that Amgen were in something of a rush when preparing the various auxiliary requests, including Auxiliary Request 11, which, it will be recalled, eventually found itself into Claim 19. While there is something in the point, I am not very impressed by it. In the first place, Amgen had overnight to consider the various auxiliary requests, and their team was very substantial consisting of many experts, including Mr Borun, Mr Brown and a number of patent lawyers. Quite apart from this, it is not as if Amgen’s attention in connection with the appeal had been drawn to the first paragraph of Example 10 for the first time the day on or before which Auxiliary Requests were drafted. As I have mentioned, attention had been focused on Example 10, and in particular the performance of various EPOs on SDS-PAGE, well before that.
121. Reliance is placed by Amgen on the fact that, after the Patent had been granted in its present form, a clear copy of a page of Dr Egrie’s notebooks (a page which was included in the File) was obtained showing, inter alia, the performance of COS rEPO against Goldwasser uEPO much more clearly than any copy which had been available to Amgen and its advisers in the context of pursuing the Patent applications. It is contended on behalf of Amgen that this better copy supported Amgen’s case on error (a), in that it arguably showed that COS rEPO had, albeit only to a small extent, a higher apparent molecular weight by SDS-PAGE than Goldwasser uEPO.
122. In my judgment, that point takes Amgen no further forward. First, the clear copy was never made available to anyone acting for or on behalf of Amgen in connection with the drafting or the pursuing of the Patent applications: that is self evident by virtue of the fact that it only came to light after the Patent was granted in its final form. Secondly, nobody at Amgen thought that this experiment showed that COS rEPO had a higher apparent molecular weight than any urinary EPO; that is clear from Dr Egrie’s notebooks, the papers published by Amgen scientists, the deposition and declaration evidence of Dr Egrie in the US, and the brief in the US Interference Proceedings. Thirdly, although this clear copy was relied on by Amgen at the hearing before me in 2001 to support the accuracy of the statement in the first paragraph of Example 10 relating to the performance of COS rEPO, I was satisfied, both from the face of the document and in light of the evidence of Professor Matsudaira, called by HMR as an expert witness, that, as Dr Egrie herself thought at the time, COS rEPO performed identically on SDS-PAGE to Goldwasser uEPO. The only evidence to the contrary was that of Professor Cummings, an expert witness called on behalf of Amgen, whose evidence on the topic I found unconvincing. While I acquitted him of intentionally misleading the court, I thought that he was partisan and had lost the detachment that one would expect of an expert witness.
123. To justify their stance in relation to error (a) as at the hearing before the Appeal Board, Amgen also rely upon the fact that evidence supporting the differential performance of recombinant EPO and urinary EPO was given to the Board on their behalf by Dr Strickland and by Professor Cummings (both of whom gave evidence in the action before me in 2001; Dr Strickland was also a witness in the present applications). I do not consider that that assists Amgen in relation to error (a). So far as Dr Strickland’s experiments relating to recombinant EPO were concerned, they were limited to CHO rEPO: accordingly, none of his evidence was relevant in relation to error (a), which, of course, is concerned with COS rEPO. Further, he did not suggest in his evidence that he had the view, let alone that he had expressed the view, that COS rEPO would, for instance, perform the same as CHO rEPO relative to urinary EPO. So far as Professor Cummings is concerned, it is true that, in his evidence before me in 2001, he expressed the view, based on the recently available clear copy from Dr Egrie’s notebooks, that COS rEPO seemed to have a slightly higher apparent molecular weight by SDS-PAGE than Goldwasser uEPO. However, I do not consider that assists Amgen. First, I had little hesitation in rejecting his evidence; secondly, his evidence was in any event based on the clear copy which was not available until after the decision of the Appeal Board.
124. Nor do I consider that the evidence given by Professor Cummings before the Appeal Board assists Amgen. He expressed the view that the SDS-PAGE experiments in the published papers to which I have referred “show that the rEPO and the uEPO samples migrate to similar regions, but they do not precisely co-migrate”. To my mind, this falls quite a way short of providing any support for the proposition that one particular rEPO, namely COS rEPO, has a higher apparent molecular weight than prior art urinary EPO, particularly in light of the fact that the papers to which he referred unequivocally suggested the contrary. Further, although Professor Cummings provided a “summary of differences between rEPO and uEPO” which included the statement that “SDS-PAGE analysis shows a difference”, that cannot have been the basis for justifying the statement in the first paragraph of Example 10 that COS rEPO has a higher apparent molecular weight than urinary EPO.
125. Amgen also rely on the fact that their European Patent agent, Mr Brown, of whom HMR make no criticism, was a party to the deliberations of Amgen in 1994, and indeed in relation to the European Patent generally. I do not think that assists Amgen. Mr Brown does not appear to have been asked to consider, or to have had cause to consider, the question of whether there was any support for the contents of the first paragraph so far as Amgen’s own work or evidence was concerned. He was entitled to assume that Mr Borun had done a proper job in November 1984 in this connection.
126. The final point relied on by Amgen in connection with error (a) in 1994 is that a number of the Opponents before the Appeal Board did not challenge the accuracy of the statement in the first paragraph as to the relative performance by SDS-PAGE of COS rEPO against urinary EPO. I reject that argument. First, at least one of the Opponents appears to have challenged this suggestion. Secondly, it may not have been to the advantage of some of the other Opponents to challenge the statement, bearing in mind that their commercial interest could have been best served by maintaining that there was a difference between the apparent molecular weight of all recombinant EPOs and all urinary EPOs. Thirdly, given that the SDS-PAGE experiments in the first paragraph of Example 10 may only have been seen to assume centre stage importance after the formation of Amgen’s Auxiliary Requests, the Opponents may well not have had much time to deal with this point or to consider the implications of Claim 19 as drafted in accordance with that request. Fourthly, it is by no means clear precisely what evidence was available to the Opponents, and the extent to which any such evidence could have been used. Thus, while it is clear that Dr Fritsch and other representatives of GI would have been aware, for instance, of the contents of the File during the Interference Proceedings in 1990 and 1991, they would not necessarily have appreciated its significance during the hearing before the Appeal Board in 1994. Further, as Mr Kitchin points out on behalf of HMR, it is far from clear that the Opponents would have appreciated that there were in fact no experiments or expert views available to Amgen to support what was said about the performance of COS rEPO in SDS-PAGE experiments. Finally, I am ultimately concerned with the skill and care employed by Amgen and their advisers, not the conduct of the Opponents at the Appeal Board hearing.

Error (b)

127. Error (b) is based on my finding, again consistent with Dr Egrie’s conclusion, that, while CHO rEPO had a higher apparent molecular weight by SDS-PAGE than Goldwasser uEPO, it had the same apparent molecular weight by SDS-PAGE as Lot 82 and Therapeutics uEPOs. On that basis, HMR argues that the statement in the first paragraph of Example 10, at least to the extent that its suggested that CHO rEPO had a higher apparent molecular weight than urinary EPO was wrong, because, while it had a higher apparent molecular weight than one type of urinary EPO, it had the same apparent molecular weight as two other types of urinary EPO. Subject to the question of whether Lot 82 uEPO and/or Therapeutics uEPO were “pooled” urinary EPO, it seems to me that error (b) is established. As I have said, that is accepted by Amgen for the purpose of the present applications, albeit that they are appealing my decision.
128. It might appear at first sight that the arguments relating to error (b) are very similar to those relating to error (a), and therefore that the same conclusion should apply, namely that, judging the matter in 1984 and in 1994, the inclusion of error (b) in the first sentence of Example 10 was attributable to lack of skill and knowledge. However, there are differences, which to my mind are not merely significant, but which lead to the conclusion that error (b) cannot fairly be attributable to lack of reasonable skill or knowledge on the part of Amgen and its advisers, including Mr Borun.
129. First, there was clear evidence in the File to support the contention that CHO rEPO did manifest a higher molecular weight by SDS-PAGE than at least one sample of urinary EPO (namely Goldwasser uEPO) and, indeed, that it did so on more than one occasion. Indeed, to that extent, unlike error (a), Dr Egrie’s recorded view was consistent with error (b). Secondly, there was plainly a reasonable basis for concluding that the other urinary EPOs, indeed those urinary EPOs which seemed to have a similar apparent molecular weight as CHO rEPO, namely Lot 82 uEPO and Therapeutics uEPO, could be properly regarded as irrelevant for the purpose of the first paragraph of Example 10. That is because the purpose of Example 10 is to found a basis for the limiting words at the end of Claim 19, and that limitation is to distinguish the recombinant EPO’s claimed from prior art urinary EPO.
130. In this latter connection, there are two points. The first, and probably less significant, point is that it does not appear that Lot 82 uEPO came from a “pooled source”, and it is unclear whether Therapeutics uEPO came from a “pooled source”. A “pooled source” means more than one human source, and it will be noted that the relevant sentence in the first paragraph does indeed refer to “pooled” urinary EPO (whereas the limiting provision at the end of Claim 19 does not). Secondly, while I took a different view, it appears to me that it was perfectly reasonable for Amgen and their advisers to have considered that Lot 82 uEPO and Therapeutics uEPO were irrelevant because they did not in fact represent prior art EPO so far as the Patent was concerned, and that they were therefore irrelevant for the purposes of novelty, and could effectively be discarded.
131. As to this latter point, two issues arise. The first issue is the relevant priority date for the purpose of Claim 19, and in particular the closing part thereof as finally settled pursuant to the decision of the Appeal Board in accordance with Auxiliary Request 11. In light of the Opinion of the Enlarged Appeal Board in G002/98, given on 31st May 2001, it appears to me that the relevant priority date in connection with this aspect of the Patent, namely claim 19 in its final form, was 30th November 1984, the date of the filing of the fourth US Patent application, because it was only then that the teaching which formed the basis of the limitation at the end of Claim 19 was revealed in the three paragraphs of Example 10. However, I do not consider that that point was by any means clear prior to that decision of the Enlarged Board. As I see it, there were reasonable grounds for thinking that, as the closing words of Claim 19 in its final form represented a limitation on the Claim, an earlier date, namely the date of filing of the first US Patent application could still be relied on as the priority date for the whole of Claim 19: see, for instance, the decision of the Appeal Board in G1/93 “Limiting Feature/ADVANCED SEMI-CONDUCTOR PRODUCTS” - OJ EPO 1994, 541.
132. So far as the second issue is concerned, it appears to me by no means clear whether Lot 82 uEPO or Therapeutics uEPO were part of the prior art, although I held them to be so. In this connection, it seems to me that Amgen are quite justified in relying on the fact that the Rapporteur to the Appeal Board (“the Rapporteur”) relayed the view that Lot 82 uEPO was not prior art, and made that clear to Amgen. On 25^th August 1994, the Rapporteur wrote a fairly detailed letter to Amgen’s European patent agents, expressing the clear view that, in order to determine whether Amgen’s recombinant EPO was novel, it was necessary to limit the comparison with urinary EPO obtained by “unmodified prior art methods”. He went on to describe Lot 82 uEPO as having been made pursuant to a “substantial modification of the Miyake method [used to produce Goldwasser urinary EPO and was] therefore not applicable in general”.
133. So far as Therapeutics uEPO is concerned, I consider that Amgen were entitled to take the view that the same conclusion applied. There is very little evidence as to how Therapeutics uEPO was manufactured, and I am not persuaded that it would have been prior art uEPO as at 30^th November 1984, if the reasoning of the European Patent Office as to Lot 82 uEPO is correct. The evidence is lacking to show that it was available, other than through private or confidential sources, at the priority date even if one takes that date as the filing of the fourth US Patent application.
134. It was argued on behalf of HMR that notwithstanding the communicated view of the Rapporteur, Amgen should have suggested to the Appeal Board that Lot 82 uEPO was in fact prior art, either because it was available before the relevant priority date or (as I held in the judgment of 11th April 2001) because it represented a workshop modification to what was undoubtedly prior art, and it therefore also constituted prior art. Even bearing in mind the obligation of a patent agent, and indeed of an applicant for a patent, to draw the attention of the Patent Office to information or documentation which is relevant and may affect the question of the validity of the patent or some of its claims, I think that that submission involves imposing on Amgen and their advisers a much greater responsibility than is appropriate. It seems to me likely, and Amgen and their advisers were entitled to assume, that the view expressed by the Rapporteur to the effect that Lot 82 uEPO did not represent prior art and should not be referred to in relation to the Patent, was a considered and informed opinion. It was therefore a view which Amgen were entitled to accept and to rely on.
135. In this connection, while the duty of candour on an applicant for a patent and its patent agent is undoubted and important, one should not carry it too far. As was pointed out in General Tire & Rubber Co. –v- Firestone Tyre & Rubber Co. Ltd [1975] RPC 203 at 269, “It is, after all, the function of a patent agent to argue in honesty for the width of the application”. More recently, Pumfrey J said in Nutrinova at [2000] FSR 831 at 835-6 that:

“It must always be remembered that it is the task of the patent agent to exercise his skill to apply to obtain as wide a coverage for the invention which is disclosed to him by the inventor as the state of the art known to him at the time of the application would reasonably warrant.”

136. Furthermore, in relation to the performance of CHO rEPO, there was additional evidence which was presented to the Appeal Board, in the form of a report on experiments by Dr Strickland. It is clear that his research, as presented, indeed confirmed Dr Egrie’s research to the effect, that CHO rEPO had a higher apparent molecular weight, on SDS-PAGE, than certain urinary EPO, and in particular Goldwasser uEPO.
137. In all these circumstances, I am of the view that the presence of error (b) in the Patent as approved by the Appeal Board is attributable to Amgen in the sense that they did not draw the attention of the European Patent Office to the performance of CHO rEPO as against Lot 82 uEPO and Therapeutics uEPO, but that their failure to do so cannot be criticised. An applicant for the Patent, using proper skill and care, could reasonably have decided, as indeed the European Patent Office itself decided, that these types of urinary EPO were irrelevant even for the purpose of comparison with recombinant EPO in the context of the experiments described in the first paragraph of Example 10, and, indeed, in light of the qualification to Claim 19 as expressed in Auxiliary Request 11. Even if Amgen had taken a different view from the European Patent Office, they were entitled to take advantage of the considered view expressed in the letter of 25^th August 1994, unless it had been apparent to Amgen that the Rapporteur was under a misapprehension or was not aware of some relevant fact. There is no suggestion of that.
138. It is fair to say that there is nonetheless an argument for contending that Amgen were guilty of want of reasonable skill and knowledge in relation to error (b) in 1984 as they did not have the benefit of the letter of 25^th August 1994 from the Rapporteur, or any equivalent communication from the USPTO, at the time. Despite that, I am of the view that error (b) did not involve a culpable failure on the part of Amgen in 1984. There was an arguably justifiable basis for error (b), namely that communicated by the Rapporteur in August 1994. Further, the circumstances in which error (b) was written in 1984 are, unsurprisingly, pretty unclear, and there are (and presumably were) question marks over the general availability and pooled nature of Lot 82 uEPO and Therapeutics uEPO. It would, in these circumstances, be unfair to characterise the mistake in 1984 as due to want of reasonable skill or knowledge, even bearing in mind that the onus is on Amgen.
139. HMR nonetheless point out that Amgen relied on the fact that CHO rEPO seemed to have the same apparent molecular weight as Lot 82 uEPO, and Therapeutics uEPO when it suited Amgen, and that this demonstrates that Amgen did not in fact believe that these urinary EPOs were to be excluded from comparison with Amgen’s recombinant EPO on the basis that they were not prior art. I think it is quite irrelevant that Lot 82 uEPO or Therapeutics uEPO were apparently referred to as comparators in the IND or the PLA, which were submissions to the FDA. That is because the question of whether those urinary EPOs were or were not prior art would have been wholly irrelevant to the issues before the FDA. While it is true that reliance was placed on the performance of CHO rEPO on SDS-PAGE against Lot 82 uEPO before the USPTO in the evidence of Dr Strickland on behalf of Amgen, it seems to me that, this is not necessarily inconsistent with Amgen’s case. They could have been putting in this evidence merely to confirm the contention that recombinant EPO’s performance on SDS-PAGE experiments was consistently very similar to the performance of urinary EPOs, irrespective of the precise source of those latter EPOs. Further, the fact that they relied on experiments against arguably non-prior art EPO in the USPTO does not of itself mean that they were in breach of their duty of candour of their duty to use proper skill and knowledge in not putting forward such evidence to the European Patent Office, or in relying on error (b) in the European Patent Office, or even in the USPTO.

Error (c)

140. Error (c) can be dealt with more shortly. Not long before the filing of the fourth US Patent application and the application before the European Patent Office, Amgen arranged for samples of recombinant EPO made in accordance with the teaching of the Patent to be sent to a Dr Yu of Yale University. This was because, according to Dr Lin, there was no one in his laboratory “with expertise in determining the carbohydrate constitution of glycoproteins”. Dr Yu analysed samples of urinary EPO, and of recombinant EPO made in accordance with the teaching of the Patent, and reported to Amgen that the results of his experiments were as recorded in the second paragraph of Example 10. These results were reported shortly before the filing of the fourth US Patent application and the application for the grant of the Patent to the European Patent Office. Because no one at Amgen had expertise in the carbohydrate composition of glycoproteins, the fact that Dr Yu’s reported results were inaccurate was not appreciated by anyone at Amgen, or indeed by Dr Borun. It appears that it was only during the Interference Proceedings, namely sometime in 1990 or 1991, that Amgen appreciated the error. During the appeal process before the Appeal Board, but well before the hearing in September 1994, Amgen conceded that the experiment reported in Example 10 was inaccurate, and indeed the Appeal Board described it as admittedly “wrong and unreliable” in its decision in November 1994.
141. So far as I am aware, there has never been any explanation as to how Dr Yu can have arrived at or recorded what are now admitted to be plainly wrong figures, or, to be more precise, one egregiously wrong figure (namely the figure of 15.09 for Hexoses in relation to recombinant EPO) in his analyses. Given that nobody within Amgen had the requisite expertise, and there is no basis for criticising Mr Borun in this connection, it seems to me that it cannot be said that any employee or representative of Amgen demonstrated a want of reasonable skill and knowledge in connection with error (c).
142. However, HMR argues that that does not determine the issue of reasonable skill and knowledge in relation to error (c). First, as I have already mentioned, Dr Yu, who for this purpose could be said to be an agent of Amgen, and who is self-evidently a carbohydrate analyst of experience, had made an error for which there is no explanation and which was translated into the Patent as drafted and as initially granted by the Examining Division and upheld by the Opposition Division. HMR say that, on the face of it, therefore there was an apparent lack of skill and knowledge which has not been explained by Amgen, on whom the onus lies.
143. Secondly, HMR says this in answer to the contention raised by HMR in the 2001 proceedings that the subsequent deletion of the first paragraph from Example 10 resulted in what might at least superficially appear to be a paradoxical contention of added matter, Amgen submitted that it should have been obvious to the notional addressee or reader of the Patent that the carbohydrate analyses of recombinant EPO in the first paragraph were inaccurate. I accepted that submission. In those circumstances, there is some apparent attraction in the argument that, in so far as error (c) is concerned, the Patent was not drafted with reasonable skill and knowledge. In effect, if one concludes that the notional addressee of the Patent would have appreciated that a particular passage was wrong, then one is saying that the error concerned is or should be obvious to the person or group of persons to whom the Patent is notionally addressed. On that basis, one must have some sympathy with the apparent logic and symmetry of the suggestion that the obverse of that conclusion is that there was want of reasonable skill or knowledge in drafting that particular passage of the Patent. If the error is obvious to the notional reader, then, at least in the absence of special facts or an explanation, it is said that it should be obvious to the actual writer.
144. These arguments have obvious attraction. However, I have come to the conclusion that they should be rejected. I am ultimately concerned with the question of whether the inclusion of error (c) involved a want of reasonable skill or knowledge on the part of Amgen and this would include Mr Borun as the individual responsible for drafting the Patent. It was positively creditable for Amgen to have taken the view that none of their employees had the skill to carry out the carbohydrate analysis in question, and no criticism can, or has, been made of them in having contracted out that exercise to an apparently competent expert, Dr Yu. It is not suggested, other than by reference to the notional addressee of the Patent, that his mistake should have been obvious to Amgen or Mr Borun.
145. There is no warrant, in my view, for equating all the components of skill and knowledge to be expected of the notional reader of a Patent to the actual writer of the Patent, even accepting that the writer under section 63(2) is treated as extending to the patentee, its employees and its patent agent. There is nothing to suggest a departure from reality when asking whether the patentee was guilty of want of reasonable skill and knowledge under section 63(2). The Statutory language and the authorities appear to require the court to take the patentee and his patent agent as it finds them, albeit that one obviously is entitled to expect them to be honest and to expect the patent agent to be “properly instructed” and professionally competent (see the guidance given in Chiron (No. 7) at [1994] FSR 458 at 467 to 468).
146. In these circumstances, I am of the view that error (c) did not result from want of reasonable skill or knowledge on the part of Amgen.

Want of good faith

147. In light of my conclusion so far, the contention that there was want of good faith on the part of Amgen and/or its agents primarily applies to error (a). I have concluded that, although error (b) was a mistake, it was based on a view which appears to me to have been reasonable and defensible. This is mainly because Lot 82 uEPO and Therapeutics uEPO were arguably not prior art and were therefore irrelevant. Indeed, this was a view which the European Patent Office had adopted and, indeed, had specifically communicated to Amgen in August 1994. It is also because they may not have been “pooled”. HMR has never contended that error (c) involved want of good faith on the part of Amgen.
148. The contention that, when drafting and filing the fourth US Patent application towards the end of 1984, and thereafter supporting the European Patent application, particularly during the hearing before the Appeal Board in September 1994, Amgen, in particular through Mr Borun, but also through Mr Odre, were guilty of bad faith in relation to maintaining error (a), is strongly, understandably and ably pressed by Mr Kitchin on behalf of HMR. First, as at November 1984, Mr Borun had not been supplied with any evidence to support error (a), and, indeed, had been provided with tolerably clear, unequivocal and first hand evidence (namely the contents of the File) which showed that error (a) was indeed wrong. Secondly, during the subsequent ten years, and in particular during the course of the interference proceedings and Chugai litigation, a number of further documents and items of evidence came to the attention of Mr Borun which underlined that error (a) was indeed a mistake. Thirdly, when it suited Amgen to do so, namely in the brief in the interference proceedings and in their IND and PLA before the FDA, they appear to have mounted a case directly contrary to what was said in error (a). Fourthly, the issue was not a background matter: performance of COS rEPO, as well as of CHO rEPO, as against urinary EPOs on SDS-PAGE was a matter of debate, evidence and in argument, in writing and orally, particularly before the Appeal Board. Fifthly, Amgen had an obvious motive or incentive to maintain error (a), particularly before the Appeal Board, but also before the Opposition Division and the USPTO, because, without it, there was, to put it at the lowest, a real risk that all or most of the protein Claims of the Patent would fail for want of novelty, i.e. because of an inability to distinguish recombinant EPOs, made according to the teaching of the Patent, from prior art, namely urinary EPO. Finally, HMR relies on the contention that Mr Borun was a dishonest witness, and, if not dishonest, Mr Odre was a very poor witness.
149. The factual basis and force of some of these points is unanswerable, in my judgment. In particular, it seems to me that, in and between 1984 and 1994 there was no evidence to support error (a) and increasing evidence became available to Amgen and indeed to Mr Borun, to show that it was a mistake. Further, it appears to me clear that the significance of the first paragraph of Example 10 should always have been a factor in the minds of Amgen and their advisers: it was plainly significant and it was the subject of evidence and argument in the USPTO as well as before the European Patent Office. However, the force of some of the points relied on by HMR is not quite as strong as might first appear.
150. While it was undoubtedly in Amgen’s interest to maintain the accuracy of error (a), that point must not be overstated. First, at least until the mistake in Dr Yu’s carbohydrate analysis was discovered, there were grounds in the Description of the Patent outside the first paragraph of Example 10 to support a novelty argument, namely error (c). However, error (c) does not assist Amgen after 1991, because, by then, they had learnt of the inaccuracy of the carbohydrate analysis. Secondly, in light of the fact that I have rejected any want of skill or care on the part of Amgen in relation to error (b), Amgen could still justifiably rely on the fact that CHO rEPO had a higher apparent molecular weight than what the European Patent Office had held to be the only type of prior art urinary EPO against which it had been run on SDS-PAGE, namely Goldwasser uEPO. Indeed, Amgen were entitled to rely on the evidence of Dr Strickland, to the USPTO and to the European Patent Office (including the Appeal Board), to the effect that he had carried out SDS-PAGE experiments on CHO rEPO which confirmed Dr Egrie’s conclusion that CHO rEPO had a higher apparent molecular weight than urinary EPO, or at least urinary EPO prepared according to what Amgen reasonably believed, and indeed the European Patent Office believed, was the only prior art urinary EPO. There is also the point that CHO rEPO was, in practice, much more important than COS rEPO. Indeed, particularly by the time of the hearing before the Appeal Board in September 1994, it had been long apparent, as I understand it, that the manufacture of EPO in accordance with the teaching of the Patent was commercially very effective in CHO cells, but was of very limited value in COS cells.
151. While it is true that Amgen contended before the FDA that there was no distinction in the apparent molecular weight and other characteristics of recombinant EPO and urinary EPO, it does not appear to me that such a contention could fairly be said to be inconsistent with what is contained in the first paragraph of Example 10. One would not be comparing like with like. As I have already mentioned, Amgen were entitled to take the view, which may be different from the conclusion I reached but was the same as that communicated by the Rapporteur in August 1994, namely that the only relevant prior art urinary EPO was Goldwasser uEPO. Accordingly, it was proper, and consistent with reasonable skill and knowledge, for Amgen not to refer the Appeal Board to the fact that CHO rEPO had the same apparent molecular weight by SDS-PAGE as Lot 82 uEPO or Therapeutics uEPO, because they were not, on this hypothesis, prior art. On the other hand, as I have already mentioned, the fact that a particular urinary EPO was prior art was irrelevant from the point of view of the FDA. In those circumstances, it seems to me that it was quite consistent for Amgen to inform the FDA that their recombinant EPO, which would have been (or at least would have included) CHO rEPO, had the same characteristics as urinary EPO, because CHO rEPO did indeed have the same apparent molecular weight by SDS-PAGE as Lot 82 uEPO and Therapeutics uEPO.
152. HMR’s reliance on the contents of the brief in the interference proceedings plainly has greater force. The passage in question must put beyond argument the contention that, by 1994, Amgen and Mr Borun were well aware of the conclusion that Dr Egrie had reached as to the performance of COS rEPO against pooled urinary EPO. Further, when it suited Amgen to rely on her conclusion, Amgen said so. However, it nonetheless remains the case that what is stated in the brief was entirely true, and had indeed been before the USPTO, namely Dr Egrie’s views on the performance of COS rEPO on SDS-PAGE against Goldwasser uEPO.
153. I turn to HMR’s reliance on the performance of Mr Borun and Mr Odre in the witness box. As already mentioned, I found Mr Borun a singularly unimpressive witness. He manifested many characteristics which can be fairly relied on to support the contention that he was not an honest witness. However, I have reached the conclusion that his unreliability in the witness box was ultimately due to a combination of his being a naturally poor witness, his lack of any clear memory of what happened in 1984, his fairly selective memory of what happened in 1994, his appreciation of the apparent difficulty he had in justifying his drafting and subsequent support of the first paragraph in light of the contents of the File, the feeling of a need to justify this drafting and support, and a relatively high ability to deceive himself that what he wanted to have happened did happen. Taking into account the totality of his evidence, and the cogent criticisms made of him by Mr Kitchin, I have come to the conclusion that Mr Borun was not a dishonest witness, in the sense of giving evidence which he knew to be untrue.
154. While criticisms were advanced of Mr Odre, I do not consider that his honesty as a witness was successfully impugned either. He was a somewhat combative witness who, in common with some other lawyers, found it difficult to remember that he was meant to be giving factual evidence rather than arguing his clients’ case. In particular HMR says he was less than honest when he refused to accept that Lot 82 uEPO had been relied on in one declaration (that of Dr Strickland) filed on behalf of Amgen in the USPTO, and this at least could be said to have been inconsistent with their case that urinary EPO was not prior art. While there is undoubtedly something in the criticism as to the way in which Mr Odre dealt with the point, I do not consider that it justifies rejecting his evidence generally. Two other criticisms of him, namely that he refused to agree that Amgen had told the USPTO that they accepted that recombinant EPO could not be precisely defined, and that he gave inconsistent evidence about the confidentiality of documents disclosed in the USPTO and in the US proceedings, do not seem to me to take matters much further. As to the former point, it appeared to me that, in the relevant submission to the USPTO, Amgen’s point was that it was not possible to define in detailed and specific terms the difference between all recombinant EPOs and urinary EPO. This is not inconsistent with their case to the USPTO, or indeed the European Patent Office: indeed it is what the Appeal Board concluded in 1994. As to the second point, Mr Odre, in common with many witnesses, initially expressed a generalised view in somewhat imprecise terms, which he subsequently qualified, again in somewhat imprecise terms. Mr Odre was also criticised for his support of a patent which contained the first paragraph of Example 10, but it appears to me that the detailed drafting of the various US Patent applications was left to Mr Borun, and I do not think that Mr Odre’s involvement really takes matters further, because he was not so concerned with the details himself.
155. In any event, what ultimately concerns me here, is not the honesty of Mr Borun or Mr Odre in their respective evidence, but whether the first paragraph in Example 10 was drafted in good faith in 1984, and whether it was, as it were, supported in good faith in 1994, and whether Claim 19 was accordingly drafted in 1984, and supported and re-drafted in 1994, in good faith. The honesty or otherwise of Mr Borun, or indeed Mr Odre, as a witness in the present applications can only be of indirect relevance in that connection. Even if I concluded that Mr Borun was downright dishonest as a witness, it would not establish that he had been guilty of bad faith in 1984 or 1994. However, I accept that it would assist that contention, because it would establish that he was a person who was prepared to lie, and also that he may well have been lying because he had something to conceal in connection with his conduct about which he was given evidence. While, as indicated, I do not think he gave dishonest evidence, the overall impression given by Mr Borun as a witness certainly does not assist Amgen in discharging the onus which section 63(2) imposes on them of establishing good faith.
156. I find the question of whether Amgen, essentially through Mr Borun, lacked good faith when drafting the first sentence of Example 10 by no means easy to decide. I have already referred to the reasons advanced by HMR as to why it is likely there was bad faith on the part of Amgen in 1984 and in 1994, and there is also the puzzling fact that there simply appears to have been no evidence to support the proposition embodied in error (a): that could be said to render it comparatively easy to conclude that it must have been made up by the draftsman, Mr Borun, which is pretty close to amounting to bad faith without further ado.
157. On the other hand, I do not find it difficult to believe that the original inclusion of error (a) in the first paragraph of Example 10 in 1984 was simply due to a misunderstanding or oversight on the part of Mr Borun. While I accept that it is difficult to explain specifically how such a mistake could have occurred, there are, I think, three points to bear in mind. First, one is talking about events that took place over 17 years ago, and it is not impossible that there was some sort of discussion with Dr Egrie, or some reading of the File, which led Mr Borun to have a wrong recollection or make a wrong note, which he has now forgotten or lost. Secondly, the recording of wrong facts in a document is almost always difficult to explain after the event: people make honest mistakes in all areas of life, and, after the errors are pointed out, they are often impossible to explain. Thirdly, it is not only difficult to explain an error of this sort: it is also difficult to see why it would have been included dishonestly by Mr Borun. He must have known that the US Patent application would be scrutinised and tested by the USPTO, and, bearing in mind the obvious value of the US Patent, if it was granted, he must have appreciated that it would be likely to be challenged and scrutinised by a number of interested parties (as indeed turned out to be the case: note the Chugai action and the Interference Proceedings). Further, if he was being dishonest, that must predicate that he knew what Dr Egrie had recorded in her notebooks about the performance of COS rEPO on SDS-PAGE, and he would have had no reason to think that she would not say the same thing in her evidence. To have deliberately included an important misleading statement in a patent application would therefore have been likely to have been appreciated by him as being something which would be very risky indeed for his clients.
158. Quite apart from this, it would have been very risky for him. As a patent attorney responsible for the drafting of the fourth US Patent application, Mr Borun would, I understand, have been liable for professional misconduct if he had knowingly included an inaccurate statement in a patent he was drafting. Although I have little doubt but that Amgen were important and valuable clients of Mr Borun’s firm, and although it is not unknown for some lawyers to act over enthusiastically, even on occasion dishonestly, on behalf of their clients, this would have been a particularly risky course for Mr Borun to have taken in the present case, from the point of view of both his clients and himself.
159. Furthermore, at the time he drafted the fourth US Patent application, the important point about the protein claim so far as novelty was concerned, was that the product had “an average carbohydrate composition which differs from that of naturally-occurring EPO” – quoting from Claim 40 in its original form in the European Patent application as well as the fourth US Patent application. Ignoring error (a), Amgen had the benefit of other statements in Example 10, ironically errors (b) and (c), which appear to have supported this definition of the protein product in any event. In 1984, he was not to know that they were both mistakes, and, for the reasons I have given, he cannot be criticised for that. There would have been therefore little incentive for Mr Borun to be dishonest in including error (a) save for the purpose of seeking to lay the ground for seeking to argue that COS rEPO was within the protein claims of the Patent.
160. In view of the terms, approved by the Examining Division and the Opposition Division in respect of Claim 20 (the predecessor of the ultimate Claim 19) the contents of the three paragraphs were (ironically) irrelevant to the claims of the Patent as granted initially and as upheld by the Opposition Division. It was only because of the decision of the Appeal Board in November 1994, that they again became relevant to the claims because of the terms of Claim 19 as approved by the Appeal Board – i.e. in accordance with Auxiliary Request 11. Perhaps a further irony is that the only reason any limiting words were required in Claim 19 was the view of the European Patent Office on the product-by-process claims, a view with which I disagree (see my earlier judgment at paragraphs 283-299).
161. By 1994, the situation had developed since 1984. There was still a significant degree of concentration on the three paragraphs of Example 10. That was because of the importance they had for Claim 19. Additionally, there was relevant evidence called by some of the Opponents, the fact that error (c) had been established and accepted by Amgen, and the body of evidence showing the views of Dr Egrie and other Amgen scientists about the performance of COS rEPO on SDS-PAGE. All of this can be said to make it difficult to understand how Amgen, and in particular Mr Borun, could have believed the information in error (a). However, there are countervailing factors.
162. First, as I have mentioned, by 1994 it was clear that CHO rEPO was commercially much more important than COS rEPO, and this ties in with the fact that no criticism could be made of Amgen in relation to their reliance on the information in error (b), particularly in view of the fact that it was accurate if the European Patent Office was correct in its view that only Goldwasser uEPO was prior art. Secondly, the evidence advanced by Amgen to support the contents of the first paragraph of Example 10 in relation to SDS-PAGE experiments, either related to CHO rEPO alone (as in the case of Dr Strickland’s evidence) or was expressed in rather general terms, and did not, dishonestly or otherwise, support error (a), in relation to COS rEPO (and in this connection, I have in mind the evidence of Professor Cummings). Further, so far as Dr Egrie’s evidence is concerned, Amgen and Mr Borun would have known the view of the USPTO. In deciding to accept the claim equivalent to Claim 19 in the form acceptable to it, the USPTO described her data relating to COS rEPO as being “at best ambiguous” and “thus.. not sufficient to contradict” what was in error (a). While I find that conclusion difficult to understand, at least on the evidence I have seen, it seems to me that it was not unreasonable for Mr Borun and Amgen to proceed before the Appeal Board on the basis that this conclusion was correct, or at least arguable. Similarly, the Opposition Division had considered that the Opponents’ evidence did not show that “the carbohydrate component of [human] rEPO is identical to that of [human] rEPO.
163. In addition, although they may not have been able to use it, Dr Fritsch and GI’s attorney, Mr Eisen, would have been aware of Dr Egrie’s evidence, of the papers published by Dr Egrie and others, and, probably, of the contents of the File, by virtue of their involvement in the Interference Proceedings in 1991 and 1992. In those circumstances, it seems to me that it is unlikely that Mr Borun would have pursued error (a), if he knew or believed that it was plainly wrong on the basis of evidence available to the Opponents. The risks would have been very substantial, not least in light of the evidence of Dr Conradt, which he obviously had in mind in September 1994, as it was part of the opponent’s evidence.
164. It also appears to me that, at least as at 1994, it is somewhat unrealistic to treat error (a) and error (b) as distinct, although it may be reasonable to do so as at 1984, and it may be appropriate to do so for some of the purposes of these applications. By 1994, the argument between Amgen and the Opponents involved a debate on the general question of whether recombinant EPO could be distinguished from urinary EPO, and it was concentrating more on CHO rEPO than COS rEPO, because it was in CHO cells, rather than in COS cells, that the claimed invention worked in a particularly satisfactory way. Although Mr Borun and others on behalf of Amgen would inevitably have had to think about the performance of recombinant EPOs on SDS-PAGE as against urinary EPOs, it was one among many topics which had to be considered. Additionally, while it would be quite unrealistic to suggest that consideration should not have been given to the performance of different recombinant EPOs against different urinary EPOs, there can have been no question of anyone having given the sort of very detailed consideration to the nature and ramifications of error (a) that it had been given during the six days that these applications lasted.
165. In all these circumstances, albeit not without some hesitation, I have come to the conclusion that Amgen have established that there was no lack of good faith on their part, or on the part of any of their agents, when including error (a) in the first paragraph of Example 10 in 1984, or in supporting the same in 1994, or in supporting and drafting Claim 19 in its various forms, in 1984 or 1994. A finding of lack of good faith would involve a serious criticism of Mr Borun. While the allegation only has to be made out on the balance of probabilities, I must bear in mind the gravity of the allegation and also the substantial lapse of time and the inevitable fading of memories. The onus is on Amgen to establish good faith, and they have discharged it.
166. Even though I have found that error (b) was not attributable to want of reasonable skill and knowledge on the part of Amgen, it is possible that it could still have been included owing to want of good faith on their part. In 1994, that appears to me to be a contention which should be rejected for the reasons already discussed in relation to error (b). The position as at 1984 with regard to error (b) and want of good faith is, I think less clear. However, even as at 1984, I consider that there was no want of good faith on the part of Amgen in relation to error (b). That is partly for the reasons discussed in relation to error (b) but also for some of the reasons for rejecting lack of good faith in relation to error (a). In relation to the latter aspect, I have in mind inherent improbability due to the risk of discovery, the uncertainty as to what happened in 1984, the fact that the error has to be assessed in the context of all the other issues as at 1984 and the seriousness of the allegation. Accordingly, I am of the view that error (b) was not be attributable to want of good faith.

CONCLUSIONS

Amendment or revocation

167. Given that Amgen are seeking a deleting amendment of the Patent, namely a deletion of claims 19 to 25 inclusive, on the basis that the validity of the remaining claims is unaffected by any of the conclusions I reached in my earlier judgment, it appears to me, in light of my analysis of the earlier decisions, and in particular Gerber [1994] FSR 471, [1995] FSR 492, and Oxford Gene [2001] RPC 310 that the valid claims of the Patent are enforceable, and that I should give permission to amend as sought by Amgen.
168. However, in light of the arguments advanced on behalf of HMR with regard to amendment and revocation, and because the authorities do not speak entirely with one voice, it is appropriate to consider whether I would permit the amendment if I am wrong, and the issue is one of discretion. If the decision whether or not to grant permission to make a deleting amendment is a matter of discretion, but if, as Gerber [1994] FSR 471 and [1995] FSR 492 suggests, the valid claims of a partially valid patent are enforceable in any event, then it seems to me that the power to grant the amendment will, save in the most exceptional circumstances, always be exercised. There is simply no reason, whether from the view of the patentee or any potential infringer, to refuse the amendment, and there is a good reason to grant the amendment, namely to ensure that invalid claims do not remain on the record.
169. On the other hand, if HMR’s primary position is correct, and there is not only a discretion whether or not to grant a deleting amendment, but, where the court refuses a deleting amendment, the patent must be revoked, there is no reason why the discretion should not be exercised on a more flexible basis. In the absence of the conclusion being inconsistent with authority, I would have little hesitation on the facts of the present case in concluding that permission to amend should be granted to Amgen, assuming that the question of amendment is one of general discretion, and that, if amendment is refused, the patent will be revoked. My reasons for reaching that conclusion can be expressed fairly shortly. It appears to me that refusing the amendment, with the resultant revocation of the Patent, would be a wholly disproportionate penalty for Amgen, and would be a wholly disproportionate benefit for infringers and potential infringers, such as HMR. This is because:

• Only one of the three errors was attributable to want of reasonable skill or knowledge;

• None of the errors was attributable to want of good faith;

• The first error was due to an oversight or misunderstanding on the part of Amgen’s US patent agent, the second error was only a mistake in light of my conclusion that certain urinary EPOs were extracted by workshop modifications of prior art, which was not a view shared by the European Patent Office, and the third error was that of someone to whom Amgen had reasonably entrusted some analytical work;

• The errors only impinged on six of the more than thirty Claims of the Patent;

• The errors were made in a patent which contained a very large amount of information and analysis, the rest of which has not been criticised;

• The errors do not appear to have misled anyone in a substantial way, save to the extent of HMR incurring substantial expense in relation to establishing their case on the issue, but that will be compensated in costs. In this connection, I appreciate that it cannot be established for certain that no one has suffered as a result of the errors, but no argument was advanced by HMR to suggest that that happened or unlikely to have happened.

170. On behalf of HMR, Mr Kitchin contends that I should nonetheless refuse permission to amend for three reasons. The first reason is the unsatisfactory way in which Amgen have conducted the present applications, and in particular the unsatisfactory and unreliable nature of the evidence given by Mr Borun and, to a lesser extent, Mr Odre. For the reasons already given, I accept that Mr Borun was indeed an unsatisfactory and unreliable witness, but he was not a dishonest witness; Mr Odre was not a wholly satisfactory witness, and was open to some criticism, in a way that Mr Brown (Amgen’s European patent agent) and Dr Strickland were not. However, I cannot accept that, because a patentee’s patent agent is an unsatisfactory witness, or even if he is a dishonest witness, that of itself should be enough to persuade the court to take a course which ultimately involves revoking the patent, in a case where the absence of the unsatisfactory or dishonest evidence of the patent agent, the court would not revoke the patent. This is not merely because the patentee cannot control the conduct of its patent agent in the witness box. It is more because, when giving evidence as to the drafting of the patent, the patent agent is not the agent of the patentee: he is a witness who is giving evidence about his conduct when he was an agent of the patentee. Accordingly, as a matter of principle, it seems to me that, unless it can be shown that the patentee contributed to or assisted in the unsatisfactory performance of the patent agent in the witness box, it would be inappropriate to hold the patentee liable in some way for that conduct. Quite apart from this, even if it is proper to take into account the criticisms that can fairly be made of Mr Borun (and, albeit to a much lesser extent, of Mr Odre) I do not accept that in the present case they would justify a revocation of the Patent if it is otherwise not justified, on the facts of the present case.
171. Secondly, HMR relies on the fact that Amgen wrongly persisted in seeking to justify the accuracy of error (a) at the trial in 2001. As to that, while I formed a firm view that error (a) was indeed an error, I do not think it would be right to penalise Amgen, other than by making them pay the costs in relation to the issue, for maintaining that there was in fact no error. This is not least because, by the time of the hearing before me, the clear copy of a SDS-PAGE experiment, not previously available to Amgen and their advisers, had become available, and Professor Cummings had expressed the view, which he maintained on oath, that it showed COS rEPO demonstrating a slightly higher apparent molecular weight than Goldwasser uEPO. It is true that, I rejected that evidence, and that, while I acquitted him of dishonesty, I was critical of Professor Cummings, in that I thought that he behaved more as an advocate than as an expert witness. It is, I suppose, conceivable that he was encouraged, even strongly encouraged, by representatives of Amgen to give the evidence that he did, but there is no evidence to support that. It is therefore the case that a highly experienced and respected Professor, with substantial experience and reputation in the relevant field, was prepared to say on oath that what I have held to be an error was in fact accurate. In those circumstances, I do not think that this second point assists HMR’s contention that, if I have a general discretion to refuse the amendment, I should exercise it.
172. HMR’s third argument relies on the contention that Amgen have not satisfied the requirements which have been held on a number of occasions to be required to be satisfied before an amendment is granted. I refer, of course, to the five points identified by Aldous J in SmithKline at [1989] FSR 561 at 569, subsequently approved in Hsiung [1992] RPC 497 and Kimberley-Clark [2000] RPC 422. As I have said, while it would be presumptuous or worse for me not to consider those five points in the present case, I cannot accept that, unless an applicant for amendment has satisfied all of those requirements, then in any such case the court has to refuse the amendment.
173. In the present case, HMR’s primary argument in relation to these five points is that Amgen have not been frank about the circumstances in which error (a) - and, to the extent that it can be relied on, error (b) – came into existence and came to be supported. In the sense that there has been no satisfactory explanation as to why Mr Borun made the initial drafting mistake, and why nobody at Amgen spotted it, in 1984, and no explanation as to why the inconsistency of error (a) with the documentary evidence consisting of notebooks, papers, depositions and declarations, was not properly appreciated in 1994, that is a good point. Also, to the extent that I found the person who, if he had remembered, would have been in the best position to explain, namely Mr Borun, to be an unsatisfactory witness, that contention could also be said to be made out. However, I refer back to my conclusion that, as happens with many mistakes in many areas of life, there is no explanation, other than the fact that there must have been some misunderstanding or some oversight, or, if there was an explanation, the persons who could have explained it have either forgotten or could not be called to give evidence. In those circumstances, particularly in light of my finding of good faith, it seems to me it would be disproportionate to hold that Amgen should be penalised on this ground, particularly to the extent of depriving them of the Patent, which, on the hypothesis under which I am currently proceeding, is what would happen if I refuse leave to amend. In this connection, I should add that there can be no criticism of Amgen in failing to call Dr Lin or Dr Egrie: they are out of the jurisdiction, no longer employed by Amgen and have refused to come to give evidence despite Amgen’s request.
174. Accordingly, whatever the proper approach to the question of amendment, I conclude that it would be right to permit Amgen to amend the Patent by deleting Claims 19 to 25 inclusive.

Damages, costs and expenses

175. If section 63(2) of the 1997 Act is to be construed as HMR contends, then a patentee will be deprived of the right to recover damages, costs and expenses (hereafter “Damages”) if any part of the patent concerned can be shown to have been drafted without reasonable skill or knowledge. On that basis, as I have found that the inclusion of error (a) in the Patent, as originally granted by the European Patent Office, and as subsequently upheld by the Oppositions Division and the Appeal Board, was due to want of reasonable skill and knowledge, it must follow that Amgen would not be entitled to Damages.
176. However, as stated earlier, it appears to me that the mere fact that there is one error in a specification, and that that error is attributable to want of reasonable skill and knowledge, does not necessarily mean that section 63(2) is automatically engaged. In my view, the court has to consider whether the specification was drafted with reasonable skill and knowledge, and the mere fact that one provision may not have been drafted to that standard does not of itself mean that the specification falls below that standard. Nonetheless, I would accept that, once it is satisfied that the drafting of a specific provision in the specification fell below the requisite standard, the court may take quite a lot of convincing before it concludes that the patentee has discharged the onus on it of establishing that the specification was nonetheless drafted with reasonable skill and knowledge.
177. There are undoubtedly a number of factors which can be cited to support the contention that the specification of the Patent was not drafted to the requisite standard. First, there is the fact that error (a) was not drafted with reasonable skill and knowledge in 1984. Secondly, there is my finding that Amgen and its agents also suffered from want of reasonable skill and knowledge when they maintained error (a) in the hearing before the Appeal Board in 1994, and indeed thereafter in the Opposition Division. Thirdly, the specification contained other mistakes, namely error (b) and error (c), which, while they were not attributable to want of reasonable skill and knowledge, were nonetheless mistakes related to error (a). Fourthly, error (a) was an important component in the Description which Amgen relied on when applying in 1984 for the claims which ultimately became Claims 19 to 25, and when seeking in 1994 to maintain those claims, which were themselves commercially important to Amgen. Fifthly, the very fact that the Patent was under consideration, albeit on a somewhat on and off basis, before the European Patent Office for 14 years can be said to make the want of reasonable skill and knowledge in connection with error (a) all the more marked.
178. Over and above this, there is the fact that it is very much in the public interest that every part of a specification in a patent is carefully drafted, bearing in mind that patents are public documents with serious potential consequences for members of the public, including commercial competitors of the patentee. Furthermore, human nature is such that most errors in a specification will tend to favour the patentee. There is therefore obvious force in the point that, once a patent needs amendment because of an mistake which is attributable to lack of reasonable skill and knowledge, the court is scarcely doing its duty as envisaged by section 63(2) if it is too ready to hold that the existence of one or two errors attributable to want of reasonable skill and knowledge does not prevent the patentee avoiding the consequences of the section.
179. Against that, it seems to me that the court should equally not be too ready to find that every time that a patent needs amending because it has an error which is attributable to want of reasonable skill and knowledge, section 63(2) applies. To penalise a patentee every time there is such an error, which results in the need to amend the patent, appears to me not only to fly in the face of the actual words used by the legislature, but also to be likely to lead to the imposition of a disproportionate penalty in some cases.
180. Turning to the more specific points which favour the non-engagement of section 63(2) in the present case, it seems to me that they are as follows. First, the Patent is a very long and detailed document, in which only three errors have been identified, and only one of those errors is attributable to want of reasonable skill and knowledge. Secondly, HMR did not challenge the view expressed by Mr Bannerman, a patent agent of 30 years experience, and the current president of the General Legal Commission on Biotechnology Patents. Having read the Patent as granted originally by the European Patent Office and the Opposition Division, the decisions in 1994 and 1998 of the Appeal Board, and my judgment of 11^th April 2001, he gave evidence as to various aspects relating to these applications, and concluded:

“[W]e have been looking in detail at one claim and one short passage in a long and complex specification. In my view, the skill in drafting overall was of the highest order and to end up with only the present areas of concern is to my mind, highly creditable.”

181. No reason was advanced to challenge the impartiality of Mr Bannerman or the reasonableness of this conclusion; indeed, the conclusion was not challenged. Obviously, that does not bind the court, nor does it mean that it is not open to HMR to invite the court to take a different view. However, having considered the whole of the specification of the Patent in no little detail over a period of more than four weeks last year, and having considered parts of it in relation to the present applications, my view is that, taken as a whole, the specification was well and competently drafted.
182. Thirdly, if one focuses on error (a), it appears to me that, taken on its own, it did not have a particularly wide ranging effect. Whether one considers the claim which is now Claim 19 in the form and context of the specification as drafted in the original application, or as granted by the Examining and Opposition Divisions, or as proposed to be modified by the Appeal Board, it appears to me that it could and would have been granted in the same form as it was, and indeed would have been valid, if the only objection to the claim was the inaccuracy contained in error (a). That is because, on this hypothesis, while one would treat the contents of error (a) as notionally excised from Example 10, error (b) would remain, as would, at least until it was effectively withdrawn in 1994, error (c). So long as error (c) was present, there was a basis upon which Amgen could perfectly properly contend that recombinant EPO could be distinguished from prior art EPO on the grounds of carbohydrate content. Even after error (c), and with it the whole of the second paragraph of Example 10, had been excised from the Patent, it seems to me that error (b) would still have justified granting the claim which is now Claim 19, in its various forms. That is because error (b) appeared to establish that a particular recombinant EPO, namely CHO rEPO, had a higher apparent molecular weight by SDS-PAGE than the sole type of urinary EPO which, at least in the opinion of the European Patent Office, represented prior art EPO, namely Goldwasser uEPO.
183. In my judgment, if Amgen had conceded that error (a) should be discharged because it was wrong, the Examining Division, the Opposition Division and the Appeal Board would each have nonetheless been prepared to grant the claim which has now become Claim 19 in the same form as they respectively thought was acceptable. This is because they would have concluded that, on the evidence available, at least one way of performing the invention claimed by the Patent produced a glycoprotein which could be distinguished on SDS-PAGE from the prior art. The only disadvantage to Amgen would have been that it would have been clear from their concession that, at least on the basis of their experiments, it would not have appeared that COS rEPO was within the ambit of the Claim. However, it is relevant in this connection to mention again that the commercially valuable process as described in the specification of the Patent involved manufacturing CHO rEPO, and not COS rEPO.
184. Fourthly, if error (a) had been the only error in the Patent, there would have been no need for Amgen to apply to amend the Patent. If error (b) had not been a mistake, I would simply have concluded that CHO rEPO, and any other recombinant EPO which fell within the ambit of the Patent, would fall within Claim 19, unless it had the same apparent molecular weight as, or a lower apparent molecular weight than, Goldwasser uEPO. Ironically, it is only because the Appeal Board took a different view from me on product-by-process claims, and I took a different view from the Appeal Board as to whether Lot 82 uEPO and Therapeutics uEPO constituted prior art, that Amgen need to amend the Patent and an argument can be run against them under section 63(2).
185. In this connection, however, the important point is that the reason I found Claim 19 invalid was not because of the mistake made in error (a), but because of the mistake which in my view underlies error (b). That mistake was that, at least in my opinion, the apparent molecular weight by SDS-PAGE of urinary EPOs was variable to such a significant extent that, at least on the basis of the evidence as it seemed to me, it would be impossible to be confident whether a particular recombinant EPO did in fact have a higher apparent molecular weight than any prior art urinary EPO. One might test one’s product against, say, six or seven different samples of urinary EPO, and find that it appeared to fall within Claim 19, but there would always be the possibility of there being another source of urinary EPO which manifested the same apparent molecular weight as one’s product. That problem underlies error (b), but not error (a).
186. As I hope has been made clear, errors (b) and (c), although mistakes, are not attributable to any want of reasonable skill and knowledge on the part of Amgen. Error (b) is plainly based on a view which a reasonably skilled and knowledgeable person could take, and indeed mirrors the considered view taken by the European Patent Office in its letter from the Opposition to Amgen. Error (c) resulted from a mistake made by an expert in whom Amgen had reasonably placed reliance.
187. Fifthly, it does not seem to me that the Opponents before the Appeal Board, or indeed the Appeal Board, itself were relevantly misled. In their decision of 21^st November 1994, the Appeal Board refer to the “consensus” among the Opponents that “the claims to the polypeptides lacked novelty” because “given an EPO preparation, it was impossible to establish whether it was uEPO or rEPO on the basis of the sugar composition”. The Appeal Board then referred to the evidence of a number of different expert witnesses on behalf of the Opponents, including Dr Conradt. They went on to say that the contents of the first paragraph had “not been shown to be wrong” and stated “that recombinant EPO produced from COS-1 and CHO cell expression had a higher molecular weight than uEPO”. The Appeal Board then said that Claim 19 in the form in which it had been originally accepted by the Examining Division and the Opponent Division “suggests merely that products different from uEPO can be obtained, not that there is any recognisable advantage in doing so”.
188. The Appeal Board then expressed the view that the evidence “reveals that… differences [between recombinant EPOs and urinary EPOs] can be attributed only to the particular cases under investigation and cannot be generalised to rEPO as a class”. Consistently with this view, they went on to state that Amgen had been unable to show that any of the alleged “distinguishing features for rEPO is a “universal” one for the whole class of rEPO” and therefore these alleged differences between rEPO and uEPO, which included the molecular weight difference, were regarded by the Appeal Board “as not reliable”. The Appeal Board expanded this view in these terms:

“[T]here appears… to be no certainty of getting a particular rEPO glycosylation pattern. The glycosylation patent for uEPO would also appear to depend on the time of day, and physiological status of the patient from whom it is obtained. rEPO thus appears to share with uEPO the characteristic that the carbohydrate composition is to a considerable degree a matter of chance.”

They also went on to make express reference to Amgen’s submissions to the FDA.

189. I think that two points can fairly be made about these observations. First, it is clear that the Opponents were making the point that there was much evidence to suggest that many recombinant EPOs had the same apparent molecular weight as urinary EPO. That view is reinforced if one turns to the evidence of Dr Conradt to the Appeal Board. That evidence suggested in clear terms that Amgen’s own experiments showed that COS rEPO had the same apparent molecular weight as prior art urinary EPO, and indeed Dr Conradt cited the published papers to which I have referred, as supporting that contention. Secondly, it does not appear that the Appeal Board was in any doubt as to the variability of the carbohydrate content, and hence the apparent molecular weight, of different types of recombinant EPO and urinary EPO, although of course they did not consider that the conclusions embodied in error (a) or error (b) were wrong.
190. In these circumstances, it is perhaps a little difficult to understand why the Appeal Board nonetheless allowed Claim 19 in the form proposed in Auxiliary Request 11. The Appeal Board expressed its reason shortly in these terms:

“The basis for this restriction was simply given by reference to the first paragraph of Example 10.”

As already mentioned, it seems to me that if error (a) had been excised from Example 10, but error (b) had remained, the Appeal Board would have had no good reason for reaching a different conclusion from that which they reached.

191. Bearing in mind these various factors, I have reached the conclusion that Amgen have established that the Patent was drafted with reasonable skill and knowledge. Although there was one error attributable lack of reasonable skill and knowledge, the specification as a whole was well drafted, and, taken on its own, the error concerned would not have led to the Patent being granted by the various sections of the European Patent Office (including the Appeal Board) in a form different from that which it was granted, and, indeed, it was not error (a), or the reason for my finding that it was a mistake, which resulted in my finding that Claim 19 was invalid.

CONCLUSION

192. I will therefore grant Amgen permission to delete Claims 19 to 25 (inclusive) from the Patent, and will declare that section 62(3), and indeed section 63(2), do not deprive Amgen from seeking damages, costs or expenses in relation to the Patent.
193. I should finally mention that the question of whether I should require a deletion from the first paragraph was touched on. Amgen were prepared to effect such a deletion, unless HMR then contended that the Patent should consequently be revoked on grounds of added matter. Mr Kitchin on behalf of HMR said nothing on this issue. On the evidence and arguments I have heard, there is plainly a case for saying that the reference to the performance of COS rEPO on SDS-PAGE should be removed. As at present advised, I see no need to delete the reference to CHO rEPO given that it did display an apparently higher molecular weight on SDS-PAGE than the only type of urinary EPO which, on the evidence I have heard, appears clearly to have been “pooled”. As the questions of whether an amendment to the first paragraph ought to be made, the extent of any amendment, and the consequences of such an amendment, were not really explored in argument or evidence, I do not propose to deal with them, at any rate at this stage.