England and Wales Court of Appeal (Civil Division) Decisions

IN THE SUPREME COURT OF JUDICATURE
IN THE COURT OF APPEAL (CIVIL DIVISION)
ON APPEAL FROM THE CHANCERY DIVISION
(MR JUSTICE NEUBERGER)

		Royal Courts of Justice Strand London WC2 Wednesday 22 August 2001

1. LORD JUSTICE ALDOUS: The applicants, Rohm & Haas Company, apply for leave to introduce fresh evidence in the appeal which is due to be heard later this year.
2. The patent is concerned with an invention for manufacturing water dispersible granules containing a substance called propanil, which is a herbicide. The patent was alleged to have been infringed by two processes of Collag Limited called A and B. For reasons which are not material, it was ordered that the issue of infringement of process B be tried as a preliminary issue. Neuberger J, in a judgment dated 28 July 2000, decided that it did not infringe.
3. Claim 1 of the patent is in this form:

"Process for producing a dispersible propanil granule comprising:

a) combining one or more surfactants with propanil and milling to a particle size of less than 20 microns to form a pre-mix;

b) adding less than 25 per cent by weight water and optionally a wetting agent to the said pre-mix and mixing until a paste is obtained;

c) granulating said paste thereby producing granules; and

d) drying said granules to a moisture content of less than 2 per cent by weight."

4. A crucial issue, as stated by the judge in paragraph 27 of his judgment, was:

"The first dispute concerns the meaning 'surfactant' as that expression is used in the patent in suit, and in particular the meaning of the expression 'one or more surfactants' in claim 1(a). The defendant contends that the expression is limited to amphiphiles, that it is limited to substances which perform their function in relation to two media, at least one of which is liquid. The claimant, on the other hand, argues that the expression 'surfactant' can and, in the context of the patent in suit, does include non-amphiphiles and that it extends to any substance which is active at the interface of two phases to modify the surface energy of the substrate."

5. The judge resolved that issue in favour of the defendants. He granted declarations that two materials used in process B, paselli and china clay, were not surfactants within the meaning of that word in claim 1 and, therefore, process B did not infringe.
6. I do not intend to refer to substantial extracts of the judgment but, as the judge made clear, he had before him evidence of Professor Luckham and Mr Knowles for the defendants and Professor Ryan for the claimants as to the meaning of the words "surfactant". He was also referred to definitions in scientific books, one of which supported the wider meaning attributed to that word by Professor Ryan. Having referred to that evidence, the judge said in paragraph 88 of his judgment:

"While it would be wrong to ignore definitions or uses of a particular word in text books and other publications, it can obviously be dangerous to rely upon them in a case such as this. The question which has to be determined is not what the word 'surfactant' means in abstract, let alone what it means in the context of other publications directed to a different, or at any rate wider, class of person than the person to whom the patent in suit is directed. The cases to which I have referred emphasise the danger of trying to construe a word or expression acontextually, that is outside the context of the patent in which it is found. There can be even greater danger, I think, if one is seeking to construe the meaning of a word in one context by reference to how it is used in another context.

Nonetheless, where, as here, one party is seeking to give a word a significantly narrower meaning than is suggested by the other party, some assistance may well be found in passages such as those I have cited."

7. The judge went on to analyse the definitions given in the books and he also drew attention to the statement in the Royal Society's "Chemistry Handbook" "Surfactants Europa" that "there are many definitions of 'surfactant' depending on personal preference and field of usage". The judge's conclusion was set out in paragraph 106 to 108 as follows:

"106. With the exception of the claimant's reliance on other Claims of the patent in suit, all the other factors relied on by the parties appear to me to have some force. In the end, while there are features of each factor upon which the claimant can justifiably rely, it appears to me that the balance of advantage on each factor lies with the defendant. So far as the body of the specification is concerned, the claimant does get some assistance from the fact that the draftsman says that the word 'surfactant' is used in the patent in suit 'in the broad sense'. However, the reference to surfactants being 'dispersing agents and wetting agents', particularly in light of the subsequent definitions and explanations of those terms in the specification, significantly assists the defendant. So too is the statement that the surfactant should be 'selected from the anionic, cationic and non-ionic type'. The reference to surfactants acting as dispersing agents, particularly in light of the definition and explanation of 'dispersing agents' in the patent in suit also supports the defendant's case.

107. I consider that the defendant's case is further assisted by the expert evidence. While not in any way questioning the expertise of the other three witnesses, it appears to me that Mr Knowles was the only witness who had the experience and discipline of the notional addressee, whose identity is somewhat unusually expressly suggested in the specification. He was an honest witness, whose evidence was entirely consistent and stood up to cross examination. It would be unfair on Mr Carr not to accept that he made some valid points to and about Mr Knowles, but, viewing matters overall, they do not cause me to doubt his evidence as to the understanding of formulation scientists in the agrochemical field of the word 'surfactant' and how that word would be understood at Claim 1(a) of the patent in suit, namely as an amphiphile.

108. The two text books pointed in somewhat different directions, but, particularly when one remembers the contents of the publication of the Royal Society of Chemists, it seems to me that the balance is in favour of the defendant, albeit mildly, on this score also. As I have already said, this is a comparatively minor aspect."

8. The judge went on to conclude that the defendant succeeded on the point of construction.
9. The fresh evidence sought to be introduced is in the third expert report of Professor Ryan. In that report he refers to a patent application of the defendants which was published on 27 July 2000. The inventor named is Mr Misselbrook, who was the managing director of Collag Limited and is closely associated with Agform Limited. Due to the date of publication, it did not come to the attention of the claimants until after the judgment of the judge.
10. That application relates to an invention for a process for the production of granules, in particular water dispersible and water soluble granules. It is said to be especially useful in the production of granules containing biologically active compounds and other substances, and in particular other agrochemical products, for example pesticides. Propanil is mentioned as one of those substances.
11. The perceived importance of that application is set out in Professor Ryan's report. He states:

"3. The Collag application (on page 7, lines 16-17) describes formation of a 'premix' by mixing together an active ingredient and an excipient. It goes on (on page 9, line 14) to suggest that 'suitable excipients include surface active agents (surfactants) including wetting agents and dispersing agents....'. On page 9, line 18, the Collag Application states that 'Examples of dispersing agents include....copolymers, random and block, of ethylene oxide and propylene oxide....'.

4. Copolymers of ethylene oxide and propylene oxide in block form are well known to be amphiphilic, forming micelles in water. Copolymers of ethylene oxide and propylene oxide in random form are not amphiphilic because the repeat lengths of the ethylene oxide and propylene oxide units are not normally sufficiently long to confer micelle forming properties. Random copolymers of ethylene oxide and propylene oxide are either water soluble or water insoluble depending on the relative proportions of each monomer and do not form micelles.

5. The statements contained in the Collag application support my views (expressed in paragraphs 15-25 of my Expert Report and paragraph 2 of my Second Expert Report) that a) the term 'surfactant' is synonymous with 'surface active agent' meaning any substance which segregates to a surface and alters the surface energy and b) the term 'surfactant' is not restricted to amphiphilic substances. The definition of surfactant did not change between the dates of the Patent and the Collag Application (ie between 1990 and 1999) nor has it changed to date."

12. In essence it is sought to introduce evidence of fact that copolymers of ethylene oxide and propylene oxide in random form are not amphiphilic. Further, it is said that Collag in their application described them us surfactants. From that the claimants wish the court to conclude that the word 'surfactant' in the patent in suit should be construed in the same way as in the Collag application.
13. The introduction of that evidence is resisted on a number of grounds. I need only refer to two. First, it was submitted that Professor Ryan had misunderstood the way that the word "random" was being used in the Collag patent application. In the context of that application it was not being used to refer to a non amphiphilic copolymer. That is disputed. Mr Acland, who appeared for the claimants, sought, with the aid of a further witness statement of Professor Ryan, to show that Professor Ryan's view was not disputed. I do not believe it right to accept that submission at this stage of the proceedings, but will assume the facts as stated by Professor Ryan to be correct.
14. Second, it was submitted that it was wrong and inadmissible to seek to construe the word 'surfactant' in claim 1 of the patent using the Collag application. In my view that second submission is correct. The fact that random copolymers of the polyethylene and polypropylene oxide are not amphiphilic cannot be relevant to the correct construction of the words 'surfactant' as used in the patent. The crucial element of the claimant's case for inclusion of the evidence is the assumed fact that such copolymers were described by Collag as surfactants and therefore the word 'surfactant' in the patent should be construed in the same way.
15. It is settled law that a document such as a patent cannot be construed with the aid of another document. For example, in Glaverbel SA v British Coal Corporation [1995] RPC 255 the defendants sought to introduce, as an aid to construction of the patent, a subsequent patent of Glaverbel. That submission was recorded by Staughton LJ at page 270, line 27, in this way:

"If patent 894 has the meaning which Glaverbel attributes to it, then it is contradicted by its corresponding (but later) United States patent, and also by its later United Kingdom patents. Indeed the United Kingdom patents support British Coal's construction. It is said that evidence of those documents is admissible to show self-contradiction by Glaverbel."

16. As to that submission, Staughton LJ said at page 271:

"There is plainly no estoppel in the present case - none is pleaded. If the later documents are relied on as evidence of what patent 894 means, the answer is that evidence is not admissible for that purpose, let alone evidence of subsequent transactions."

17. A similar approach was adopted by this court in Minnesota Mining & Manufacturing Co v Plastus Kreativ AB [1997] RPC 737 at p752.

"Mr Waugh who appeared for 3M drew to our attention the Shorter Oxford English Dictionary, the New Collins Thesaurus, and a number of documents in which the word opaque had been used. He submitted that they indicated that the word was not an absolute term meaning impenetrable to light. All that the word required in the claim was that, as a practical matter, the flaps would have sufficient opacity to remove the illumination gap and to obscure the contour of the holes and notes.

The documents to which Mr Waugh referred us cannot be of any help in construction of the patent. Dictionaries can provide a useful starting point, but cannot be determinative as the task laid down in the 1977 Act requires the court to seek the middle ground between 'literal' and 'liberal' construction. Thus it is to the specification that the court must turn to ascertain the sense in which a word or phrase is used and the purpose of its use.

The evidence established that the word 'opaque' when used as a technical term meant, impenetrable to light. That appears to me to be the normal dictionary meaning as stated in the Shorter Oxford Dictionary. However in this case the patent itself indicates the amount of variation from that literal meaning which is encompassed by the claim. It includes those variants which have, and the skilled reader would realise would have, no material effect upon the way the invention worked and excludes those that have and would be thought to have a material effect."

18. The judge had evidence before him that the word "surfactant" could be understood in the way suggested by the defendants. His task was to construe that word in the way directed by section 125 of the Patents Act 1977. Thus he had to have regard to the context of the specification and to pay due regard to the Protocol on Interpretation. The fact, if it be a fact, that Collag, in a patent application drafted nine years after the patent was drafted, used the word "surfactant" in a broad way cannot be admissible when construing that word in the patent.
19. No doubt the court has to be instructed as to the meaning of technical words. In this case the judge had evidence before him as to the two possible technical meanings. That was the only admissible evidence. Thereafter, he had to apply the Protocol and decide what was the ambit of the claim. In my view, the evidence sought to be adduced is not of sufficient relevance to have any material affect on an appeal. I therefore refuse the application.
Order: Application refused. Applicants to pay respondent's costs assessed in the sum of £9,200, to be paid by 4 pm on Friday 7 September. Order to be drawn up as agreed between counsel.