Neutral Citation Number: [2007] EWCA Civ 805
Case No: A3/2006/1658

IN THE SUPREME COURT OF JUDICATURE
COURT OF APPEAL (CIVIL DIVISION)
ON APPEAL FROM THE HIGH COURT OF JUSTICE
CHANCERY DIVISION (PATENTS COURT)
The Hon Mr Justice Lewison
HC 05 C02523
Royal Courts of Justice
Strand, London, WC2A 2LL

Date: 19 October 2007            

Before :

THE RT HON LADY JUSTICE SMITH
THE RT HON LORD JUSTICE JACOB
and
THE RT HON LORD JUSTICE WALL
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Between :

	Vector Corporation	Appellant	
	- and -		
	Glatt Air Techniques Inc	Respondent	

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Richard Arnold QC and Richard Davis (instructed by Withers & Rogers LLP) for the Appellant
Simon Thorley QC (Douglas Campbell was present at the 31 July hearing only) 
(instructed by Cripps Harries Hall LLP) for the Respondent

Hearing dates: 3 and 31 July 2007
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Judgment

Lord Justice Jacob:  
1.	This is my final judgment on this appeal.  It supersedes earlier drafts and an oral judgment given following argument on 31st July 2007 about the consequences of the first draft judgment.  We indicated then that the appeal would be allowed and that a final single judgment would be handed down in due course.
2.	Article 123(2) of the European Patent Convention provides:
A European patent application or a European patent may not be amended in such a way that it contains subject-matter which extends beyond the content of the application as filed.
So far as is relevant here, the Patents Act 1977 provides:

76(3)	No amendment of the specification of a patent shall be allowed … if it-
(a)	results in the specification disclosing additional matter…	 
3.	The wording is not quite the same (e.g. “matter” for “subject-matter”) but no one doubts that the meaning of s.76(3)(a) is exactly the same as that of Art 123(2).  I so held in Merrell Dow v HH Norton 1st October 1996.   Since the case is unreported, I set out my reasons again:
Section 76 must be given a purposive construction.  Its purpose is to stop patentees inserting information after filing which enables them to support their claims.  The addition of information irrelevant to claims as sought to be amended is a mere explanation which harms no one and assists the public.  There is apparently no direct authority in the United Kingdom relating to amendments of a patent specification by way of an additional acknowledgement of prior art.
However, there is a more general principle stated by Aldous J in Bonzel v Intervention (No 3) [1991] RPC 553 at 574.  He stated the test for examining whether amendment involved the adding of subject matter to be as follows:
(1)	To ascertain through the eyes of the skilled addressee what is disclosed, both explicitly and implicitly in the application.
(2)	To do the same in respect of the patent as granted.
(3)	To compare the two disclosures and decide whether any subject matter relevant to the invention has been added whether by deletion or addition.  The comparison is strict in the sense that subject matter will be added unless such matter is clearly and unambiguously disclosed in the application either explicitly or implicitly.
It will be noted that Aldous J used the expression “subject matter” whereas s 76 does not use that expression; it merely uses the expression “matter”.  Is there a difference?  Article 123 of the European Patent Convention provides [I set it out].  
It might be suggested that our draftsman in s 76 was intending to do something different from that in art 123 and more especially so because s 76 is not one of those sections which by s 130(7) of the Patents Act 1977 is expressly stated to be intended to have as near as is practicable the same effect as the corresponding article of the European Patent Convention.  However, I have come to the firm conclusion that s 76 is not intended to have a different effect from art 123.
Mr Thorley points out that any such construction could lead to a perfectly absurd result.  An amendment could be effected in the European Patent office to a patent application or, in the case of opposition proceedings, a granted patent which would be perfectly in accordance with the European Patent Convention but which, if there was a difference of meaning between s 76 and art 123, could result in invalidity here.  That is too absurd for words.  I think s 76 in this respect has exactly the same meaning as art 123.
4.	 In Richardson-Vicks’ Patent [1995] RPC 568 at 576 I summarised the rule in a single sentence:
“I think the test of added matter is whether a skilled man would, upon looking at the amended specification, learn anything about the invention which he could not learn from the unamended specification.”
I went on to quote Aldous J in Bonzel.  His formulation is helpful and has stood the test of time.
5.	The reason for the rule was explained by the Enlarged Board of Appeal of the EPO in G1/93 ADVANCED SEMICONDUCTOR PRODUCTS/Limiting feature [1995] EPOR 97 at [Reasons 9]:   
“With regard to Article 123(2) EPC, the underlying idea is clearly that an applicant shall not be allowed to improve his position by adding subject-matter not disclosed in the application as filed, which would give him an unwarranted advantage and could be damaging to the legal security of third parties relying upon the content of the original application.”
6.	Mr Richard Arnold QC provided a clear articulation as to how the legal security of third parties would be affected if this were not the rule:
The applicant or patentee could gain an unwarranted advantage in two ways if subject-matter could be added: first, he could circumvent the “first-to-file” rule, namely that the first person to apply to patent an invention is entitled to the resulting patent; and secondly, he could gain a different monopoly to that which the originally filed subject-matter justified.
7.	Kitchin J has recently helpfully elaborated upon the Bonzel formulation in European Central Bank v Document Security Systems [2007] EWHC 600 (Pat), 26th March 2007:
[97]	A number of points emerge from this formulation which have a particular bearing on the present case and merit a little elaboration. First, it requires the court to construe both the original application and specification to determine what they disclose. For this purpose the claims form part of the disclosure (s.130(3) of the Act), though clearly not everything which falls within the scope of the claims is necessarily disclosed. 
[98]	Second, it is the court which must carry out the exercise and it must do so through the eyes of the skilled addressee. Such a person will approach the documents with the benefit of the common general knowledge.
[99]	Third, the two disclosures must be compared to see whether any subject matter relevant to the invention has been added. This comparison is a strict one. Subject matter will be added unless it is clearly and unambiguously disclosed in the application as filed.
[100]	Fourth, it is appropriate to consider what has been disclosed both expressly and implicitly. Thus the addition of a reference to that which the skilled person would take for granted does not matter: DSM NV’s Patent [2001] R.P.C. 25 at [195]-[202]. On the other hand, it is to be emphasised that this is not an obviousness test. A patentee is not permitted to add matter by amendment which would have been obvious to the skilled person from the application.
[101]	Fifth, the issue is whether subject matter relevant to the invention has been added. In case G1/93, Advanced Semiconductor Products, the Enlarged Board of Appeal of the EPO stated (at paragraph [9] of its reasons) that the idea underlying Art. 123(2) is that that an applicant should not be allowed to improve his position by adding subject matter not disclosed in the application as filed, which would give him an unwarranted advantage and could be damaging to the legal security of third parties relying on the content of the original application.  At paragraph [16] it explained that whether an added feature which limits the scope of protection is contrary to Art 123(2) must be determined from all the circumstances. If it provides a technical contribution to the subject matter of the claimed invention then it would give an unwarranted advantage to the patentee. If, on the other hand, the feature merely excludes protection for part of the subject matter of the claimed invention as covered by the application as filed, the adding of such a feature cannot reasonably be considered to give any unwarranted advantage to the applicant.  Nor does it adversely affect the interests of third parties. 
[102]	Sixth, it is important to avoid hindsight. Care must be taken to consider the disclosure of the application through the eyes of a skilled person who has not seen the amended specification and consequently does not know what he is looking for. This is particularly important where the subject matter is said to be implicitly disclosed in the original specification. 
8.	When amendment of a granted patent is being considered, the comparison to be made is between the application for the patent, as opposed to the granted patent, and the proposed amendment (see the definition of “additional matter” in s.76(1)(b)).   It follows that by and large the form of the granted patent itself does not come into the comparison.   This case was to some extent overcomplicated by looking at the granted patent, particularly the granted claim 1.
9.	A particular, and sometimes subtle, form of extended subject matter (what our Act calls “additional matter”) is what goes by the jargon term “intermediate generalisation”.   Pumfrey J described this in Palmaz’s European Patents [1999] RPC 47, 71 as follows:
“If the specification discloses distinct sub-classes of the overall inventive concept, then it should be possible to amend down to one or other of those sub-classes, whether or not they are presented as inventively distinct in the specification before amendment. The difficulty comes when it is sought to take features which are only disclosed in a particular context and which are not disclosed as having any inventive significance and introduce them into the claim deprived of that context. This is a process sometimes called ‘intermediate generalisation.”
10.	None of the foregoing was controversial.   The sole question before us at present is whether the new independent claim 13 sought to be introduced by amendment does consist of extended subject matter and in particular is an intermediate generalisation.
11.	I begin by recording the context in which it arises.  The proceedings commenced with Vector seeking revocation of Glatt’s EP (UK) 0 570 546.  Glatt responded by seeking unconditional amendment.   Vector opposed the amendments on a mass of grounds, mainly discretionary but some as to allowability.  It also attacked the validity of the proposed amended claims on the basis of alleged lack of novelty and obviousness over four citations.   
12.	The trial judge, Lewison J, rejected all the discretionary grounds, held the amendments allowable in law and rejected all the attacks on validity, [2006] EWHC 1638 (Ch), [2007] RPC 12.    He granted permission to appeal in relation to the allowability of the amendments, but not in relation to the issues of novelty and obviousness.  Vector sought permission to appeal those issues.   In the event we did not reach the request because the appeal was allowed on the amendment point.
13.	Lewison J’s reason for granting permission to appeal in relation to the allowability of the amendments was that “the correct approach to the exercise of the discretion to permit amendment to patents post-grant is one that should be considered by the Court of Appeal.”  However permission was also granted in relation to added matter and extension of scope of protection.
14.	Although it was the basis for the grant of permission, Vector did not appeal about any of the discretionary grounds.  It also did not appeal the finding that the amendment to claim 1 was allowable (Judgment [102-106]).   The appeal was confined, as I have said, to the allowability of new claim 13.
15.	The field of technology of the patent is fluidised beds.   No complaint is made of the Judge’s findings at [6-25] as to the common general knowledge of the person skilled in the art, the notional reader of the specification.   I do not need to set it out again.   What I do need to set out are parts of the application as filed.   
16.	I begin with the drawings:

17.	I summarise in my own words what is shown.  There is a container 12 for the fluidised bed.  Air comes up through holes 20 in a plate 18.   There is a spray nozzle 32.   This sprays liquid into the fluidized particles so that they can be coated.   The container is provided with a so-called Wurster insert 22.   Such an insert divides the container into an “upbed” and a “downbed”.   The particles move upwards inside the insert and downwards on the outside, being recirculated at the bottom.  The system works by having less air (by fewer or smaller holes) under the downbed than under the upbed.  The Judge describes it in more detail at [19].  It formed part of the common general knowledge.  What is different from the conventional Wurster arrangement is the physical shielding 40 around the nozzle and the shielding of the spray pattern provided by the air around it.   The shielding allows the spray pattern to develop before meeting the particles.
18.	I turn back to the application.  It begins with an acknowledgment of the Wurster system.  It goes on to say:
The spray nozzle itself is shielded, preferably by being surrounded by a cylindrical partition extending from the orifice plate or screen at the bottom end of the product container to shield the spray nozzle tip.
19.	It then goes on to acknowledge some specific pieces of prior art.  I do not set it out.  Mr Arnold sought to persuade us that the prior art as described could be divided into cases which provided a structure around the nozzle which did not provide shielding and cases where there was no structure but air was provided.  I do not think that is right.  What the patentee is saying here (I know not whether rightly) is that in no case is there shielding of the spray.
20.	Under the heading “Summary of the Invention” the inventor reports the observation which led him to the invention:
It has been observed in the course of several laboratory Wurster coating trials that material, including substrate, from the fluidization or processing air stream has been drawn into the spray nozzle liquid/air jet before the spray pattern has been fully developed.  In some cases, when the material being coated has abrasive properties, it was found that the material was moving with sufficient force to cause erosion of the nozzle tip.
21.	He then puts forward his idea:
Accordingly, the present invention introduces a shielding or barrier means around the lower portion of the nozzle, within the upbed, for shielding the nozzle and allowing up flow of air within the shielding means around the nozzle.  This ensures that particles, disposed in the product container outwardly of the barrier, are prevented from entering the spray pattern before the spray pattern is sufficiently developed.  This allows the droplet density to decrease before contact therewith by the particles of the fluidized bed and, accordingly, the particle surface will be more evenly wetted preventing excessing particle agglomeration.  The liquid contact with the particles can be more precisely controlled and higher spray rates can be achieved with less agglomeration.
A principal object of this invention is to shield the spray discharging nozzle.  The shield prevents the entry of particles into the spray pattern before the spray pattern has had an opportunity to develop.
Another object of this invention is to provide an apparatus by which particles to be coated are prevented from entering the spray pattern until such time as the droplet density of the spray pattern has been substantially reduced.
Yet another object of this invention is to provide a columnar shield of upwardly moving air about the lower portion of the spray pattern formed by a spray nozzle of a Wurster system processor and wherein the shield may be adjusted vertically according to the spray pattern being discharged and the air flow velocity of the processing air.
A further object of this invention is to provide a shield such as that set forth in the immediately preceding object and whereby the vertical positioning of the shield may be utilized to alter the associated spray pattern.
Yet another object of this invention is to provide a coating zone within the upbed of a Wurster system coater whereby the coating zone is protected by a surrounding column of upwardly moving air in order to allow the coating zone to more fully develop and the liquid droplet density thereof to be substantially reduced prior to entry of particles into the coating zone.
22.	He then goes on to describe his “preferred embodiment” – that which is shown in the picture.   In the course of this he describes how shielding of the spray pattern is provided:
The partition 40, as well as the tubular column of upwardly rising air about the spray nozzle assembly, shields the lower, beginning portion, of the spray pattern 56.   The particles 60, passing upwardly through the upbed 30, are not drawn into this spray pattern.  The annular column of air thereby allows spray pattern 56 to substantially develop, and the liquid droplet density of the spray pattern is substantially reduced before particles 60 enter into the spray pattern 56.
23.	So the preferred embodiment shows a physical shield around the base of the nozzle.  What Mr Arnold called “clean air” comes up inside the shield and surrounds the spray pattern allowing it to expand before coming into contact with the particles.
24.	But then the inventor says this:
Various modifications to the above-described preferred embodiment may be utilized.  For example, a spray nozzle may be utilized in systems other than Wurster coater type systems where shielding is desirable.  Such systems may not require the spray nozzle to be upwardly disposed; the spray nozzle may be angled with respect to the major axis of the container.  The shielded spray nozzle may also be utilized without a Wurster-type cylindrical partition 22.  The shielded spray nozzle may also be within an expansion chamber instead of the product container.  Further, although an air distribution plate or screen is depicted, gas flow may originate into the processor through other structural arrangements.  In addition, although the shielding of the spray nozzle is preferably provided by an inner cylindrical partition 40, other shielding arrangements may be utilized.  For example, shielding of the spray nozzle may be accomplished by formation of an air wall or stream that surrounds the nozzle and prevents particles from prematurely entering into the spray pattern.  Alternatively, a deflector or shield may be formed integral with the spray nozzle itself to prevent particles from interfering with the developing spray pattern.
I have italicised the key passage.   
25.	To my mind this paragraph is clearly presenting alternatives to the preferred embodiment.  Apart from the italicised bit it says you can use an angled nozzle, or not use a Wurster partition, or have the spray nozzle in an expansion chamber instead of the product container or use a different system to provide the air or use a deflector shield integral with the nozzle.   All these are alternative ideas presented as within the scope of the invention.
26.	Turning now to the italicised bit, there is only one way to read it.  It clearly and unambiguously says you do not have to use the cylindrical shield around the nozzle:  instead you can use an air wall or stream to do the job of shielding.   I do not think there is any element of hindsight here.  It is what the patentee clearly proposed in his application.
27.	Mr Arnold suggested otherwise.  I do not agree, but should deal with his arguments in turn:
i)	He suggested the skilled man would not read the passage as saying gas alone would do because the acknowledgement of the prior art talked about gas alone systems.  But, as I have said, not a gas alone system which provided shielding of the spray pattern.
ii)	Next he pointed to several passages in the specification which refer to adjustment of the shield.   I have quoted one (the third “object of the invention”) but there are others, particularly in relation to the preferred embodiment which describes the adjustability of the partition 42 relative to the nozzle.  Mr Arnold suggested that such adjustability could only be provided by a physical barrier.  I do not see why, but in any event I do not see adjustability as forming a key part of the invention.
iii)	He suggested that the italicised portion was tied to the preceding sentence about gas flow other than through a plate because of the initial words “In addition”.  I do not agree.  There is no connection between the two ideas.
iv)	He pointed to the fact that there was no detailed disclosure as to how you could provide shielding using just a gas wall.  How could you get “clean air” without a physical shield?   There would have been something in this point if insufficiency had been raised as an objection to the claim.  But it was not.   
Mr Arnold suggested that because the onus lay on an applicant for amendment to justify his amendment, it followed that the onus lay on him to prove that his claim was enabled.  I do not agree.   An attack on a proposed amended claim is no different from an attack on an unamended claim.  The onus lies on the attacker in each case.
Mr Thorley QC for Glatt, ventured to suggest on this point, without any evidence, that one way one could provide an air wall would be to provide extra and/or larger holes in the plate near the nozzle.   That may be right, but it forms no part of my reasoning.
28.	So I think one of the alternatives proposed by the patentee to his preferred embodiment is an air wall shield in a Wurster type arrangement.   Such a proposal is not an intermediate generalisation and is in principle allowable.
29.	The Judge thought so too.   He put it very shortly (not surprisingly given the mass of points he was dealing with) at [107]:
Mr Davis had a separate point on claim 13 relating to added matter. The point is this. Claim 1 of the patent application as filed required the combination of both the physical shield (the means) and also the upwardly moving column of gas (the gas stream). I have held that this construction of the application is correct. Although claim 13 requires both a means and a gas stream, it is only the gas stream that shields the initial spray pattern. Thus, says Mr Davis, there is added matter, because the application does not reveal that the gas stream alone can shield the initial spray pattern. The place to look for disclosure is the specification. One passage in the specification reads [he then set out the words I have italicised and added].   In my judgment this is sufficient disclosure to support amended claim 13.
30.	Mr Arnold submitted that the Judge was inconsistent, for, when dealing with the now abandoned argument that amended claim 1 was also for an intermediate generalisation, he said:
[102]  …. So far as claim 1 is concerned, the effect of the amendment is that the claimed invention requires both the “means” and the “gas stream” to act together to shield the initial spray pattern. The application in my judgment also requires both.  It points out that in the cited prior art, some patents do not disclose protection of the spray pattern “by an upwardly moving column of air”, and others do not disclose a structure having this effect.
31.	I do not accept that the Judge was inconsistent.  Nor, if he was, does that assist Mr Arnold.   When the Judge said that the “application requires both” he must have meant “discloses both” – as indeed it does.   An application in itself cannot “require” anything.   And in any event the italicized portion is explicit, that a gas wall alone will do, as I have already said and the Judge held.
32.	So there is a basis in the application for a claim to the concept of a Wurster device provided with shielding of the nozzle by an air wall alone.   It is on that basis I approach proposed claim 13.   It reads:
“Fluidized bed processor having a product container section (12) opening downwardly into a plenum chamber (16) through a gas distribution plate or screen (18) having openings (20) formed therethrough for upward flow of fluidizing gas, particularly air, from the plenum chamber (16) into the product container section (12) for fluidizing particles (60) therein so as to form a fluidized bed, the product container section (12) including a spray nozzle (32) and a substantially cylindrical partition (22) with an upbed (30) defined therein, 
characterised thereby, that a means is provided within the upbed (30) which  means is  adapted to form in operation a gas stream that surrounds the spray nozzle (32) so that said gas stream shields in operation the initial spray pattern developed by said nozzle (32) against the entrance of particles (60) moving through the fluidized bed.”
33.	The pre-characterising portion of the claim is a bed provided with a Wurster insert.   Nothing turns on that.   The characterizing portion adds the requirement that there be a means to form a shielding gas stream.   As such I find that unobjectionable.   Given a disclosure of a shielding gas stream it adds nothing to say there should be a means to provide it.
34.	But what about the italicized words? They add the requirement that the means be within the upbed.  Mr Thorley suggested the words were mere surplusage.  I do not agree.  They add an extra requirement, namely that the means which forms the gas stream be within the upbed itself.  True it is that the means disclosed for providing the shielding by the physical wall shown in the preferred embodiment is within the bed.  But nothing is said or shown about where the means which provides the gas alone shield is to be.   So adding that the means should be within the bed adds something – and makes a combination not disclosed expressly or by implication in the specification.  It is a true unallowable intermediate generalization.
35.	What then should be the consequence of this conclusion?   Clearly the appeal should be allowed insofar as it relates to the allowability of the proposed claim 13 as it stands.    The patentees sought permission to delete the italicized words.   Vector opposed that.  Mr Arnold contended that if it were permitted, a new trial to consider the validity of this hitherto unconsidered claim would be necessary.   He relied on Nikken v Pioneer [2005] EWCA Civ 906, [2006] FSR 4 in which this Court decided that post-trial applications to amend a patent by claim re-writing should not be permitted.
36.	Mr Thorley accepted the Nikken principle.  He submits that this was one of those rare cases where no new trial would be needed, as contemplated in Nikken at [11].   So the real question we have to decide is whether that is so.
37.	Mr Arnold takes three points, each of which he says would mean a new trial.  Firstly, he says that the evidence would be different or might be different in an attack on the new claim based on the existing prior art.  Second he says there might be other prior art or an attack based upon common general knowledge which would be rather different.  Thirdly, he says that the question of the sufficiency of the proposed claim has not been considered and it is too late now.
38.	At present I am not disposed to accept the first two of these points.  I think Mr Thorley is right in saying that the judge’s conclusion as to validity did not depend in any way on the italicised words.  He concluded that a wider claim - that which Glatt now wish to propose, was valid. So, submits Mr Thorley, the larger target was not hit on the existing evidence about obviousness or anticipation.   There is no point allowing a second attack confined to the smaller target which is within that larger one. The smaller target needs no second trial about novelty or obviousness.
39.	 I am not entirely sure that is so.  Had these been the only two points that were taken, I think the better course would have been to adjourn the matter to a hearing of the appeal on obviousness and novelty.   That would have enabled the court to understand more and more clearly whether the judge’s finding that in effect there was no shielding at all in any of the cited prior art was limited to shielding which was produced at least in part by a physical shield.  Thus if only the first two points had been taken I would have been disposed to grant permission to appeal and to consider in more detail the judge’s finding about no shielding of the nozzle.  
40.	What concerned me is Mr Arnold’s third point.  There is nothing in the patent in detail about shielding by just an air wall, or how such a shielding is to be achieved in practice.  As I have pointed out claim 13, apart from the italicised words, is justified by a single sentence in the patent.  I am not confident that if the shielding means is to be air alone but not provided by a means within the upbed that the patent gives sufficient instruction as to how it is to be done.  Maybe one could just use larger holes in the gas distributor plate, but I do not know.
41.	I am afraid that I conclude that this could be the subject of a significant further debate – a fresh trial.  True it is that originally there was no attack on sufficiency, but that was when the claim called for the means to form the gas shield to be within the upbed.  I am rather sorry to come to this conclusion because the patentee’s idea of shielding the nozzle was a wide one.  But on the other hand the Nikken v Pioneer rule is a vital one for the proper conduct of patent disputes.  If parties were allowed to change their position or add new points from time to time after trial, then there will never be an end of patent litigation.  That is perhaps one of the reasons why delays of some many years occur in the European Patent Office.  
42.	Accordingly, this appeal should be allowed.  Claim 13 should be disallowed and there should be no further opportunity to reformulate.  The patentees must be satisfied with their existing claims 1 to 12.  
43.	I would add that the point about added matter in amended claim 13 was not considered by the Judge.  But he is hardly to be blamed for this.   The point was not debated at all or if so, insignificantly.  Certainly the post-judgment correspondence does not mention it which is where one would expect it to be taken.   The point was raised in the pleadings but along with a whole mass of other points which were given emphasis at trial and which in the end had no merit.    It is because they had no merit that, although the appeal has been allowed on this single point, the judge’s order as to costs in favour of the patentees was left undisturbed.
Lord Justice Wall:
44.	I agree.
Lady Justice Smith:
45.	I also agree.