This began with an application for permission to appeal. It was granted when the main arguments were over. It is now an appeal. It is from a judgment of Mr David Young QC sitting as a Judge of the Patents County Court, given on 23rd March 2005.

The essential circumstances are these. The patentees, Unilin, applied in the European Patent Office for a patent for a floor covering. The application succeeded. The UK version is EP (UK) No.1,024,234. During the course of prosecution the patentee became aware of some prior art which made it necessary for it to amend by reducing the scope of the main claim. The practice when such an amendment is made is to make corresponding amendments to the body of the specification so that the description (text and drawings) “conforms” to the main claim. An attempt to do that was made in this case.

After grant, Unilin sued three defendants for infringement of the patent. The defendants counterclaimed for revocation, raising a piece of prior art (Yoichi) which had not been cited against the patent before. By a judgment of 26^th September 2003 HHJ Fysh QC held that Claims 1-19 of the patent were invalid over Yoichi but that Claims 20 and 21 were valid and infringed. At the same time he gave leave to amend by, firstly combining the features of Claim 20 with those of Claim 1, and secondly by introducing into Claim 1 distinguishing words over Yoichi.

This Court affirmed Judge Fysh’s findings ([2004] EWCA Civ 1021). So the patent was partially valid and infringed. Unilin now seek damages for the past infringements and costs. The defendants say that s.63(2) of the Patents Act 1977 stands in their way.

This provides as follows:

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

The defendants say that the claimants have failed to prove that the patent was framed with reasonable skill and knowledge. No challenge is made as to good faith. So the issue is simply was “the specification of the patent framed with reasonable skill and knowledge”?

As can be seen from the previous judgments the patent is concerned with a floor covering consisting of panels. I set out the claim broken into integers in paragraph 11 of my judgment upholding Judge Fysh. There is no need to set it out again here. The key points to notice now are that the claim as granted contains a clear limitation that the panels should “substantially consist of HDF-board or MDF-board” and that there should be a “snap together connection”.

These limitations were not essential when the patent was applied for initially. In addition to snap-fit the patentee contemplated a locking together by merely turning. The idea was that the projecting tongue of one panel slipped into an appropriately shaped groove of the other such that the tongue could be inserted whilst one panel was at an angle to the other but when they lay flat they lay locked together. The sort of thing contemplated is shown in figures 3, 4 and 11 of the patent. Moreover, as applied for there was no limitation to the panels being made of MDF or HDF.

So the amendments to claim 1 made during prosecution were to make MDF/HDF material and snap-fit essential. An attempt was made to amend the description so that it conformed to the amended claim. The defendants say there was a failure to do this properly and that accordingly the specification was not framed with reasonable skill and knowledge. In particular it is said that there was no systematic attempt to remove all reference to non-MDF/HDF material or to purely turn-fit.

The Judge held that 2 passages in the specification referring to these features ought to have been removed and that the failure to do so amounted to lack of reasonable skill. Mr Carr QC for the defendants says he did not go far enough. On the contrary he says that quite a large part of the specification plainly refers to purely turn fit and that more than the single passage identified by the Judge as extending beyond MDF/HDF remains in the specification. He says that this is such a large scale lack of care that the patent cannot be said to have been framed with reasonable skill.

Before I go any further it is important to note that Mr Carr does not say that any of the material he says should not have been left in the specification rendered any of the claims insufficient (Art. 83 of the EPC). Nor does he suggest that any of the claims, whether before or after amendment, did not comply with the requirement of Art. 84 of the EPC:

“The claim shall define the matter for which protection is sought. They shall be clear and concise and be supported by the description.”

Nor is it suggested that any of the references to non-MDF/HDF material or purely turn fit are technically wrong. The monopoly claimed just does not extend to them.

Finally it should be noted that the reason for the subsequent amendment, namely to avoid Yoichi, has nothing whatever to do with the passages which it is said should not have been left in the specification following amendment during prosecution – there is no nexus between the alleged failure to exercise reasonable skill and knowledge and the post-grant amendment or the reason for it.

It makes sense to deal first with Mr Tappin’s submissions by way of respondent’s notice on behalf of Unilin. The Judge found that some passages were drafted without reasonable skill but that the specification as a whole was drafted with reasonable skill. Mr Tappin says the passages concerned are irrelevant to the required reasonable skill. It was not necessary and wrong for the Judge to take the passages concerned into account at all.

Mr Tappin developed his submission this way: the key duty of the patentee (or his agent) is to produce a specification which complies with the requirements of the EPC. So, for instance, the specification must comply with Art. 84. It must comply with Art 83 (disclose the invention sufficiently and clearly enough for it to be carried out by a skilled man). And of course it should not claim any matter which is either old or obvious over what is old (Arts.54 and 56). Thus if the patentee or his agent is aware, or even reasonably ought to be aware, of any relevant prior art, a specification drafted as though that prior art did not exist would probably be drafted without reasonable skill and knowledge (and in an extreme case, without good faith).

Apart from compliance with the EPC, Mr Tappin would accept that a specification ought not to contain misleading information. So if such information is there by reason of a failure to exercise reasonable skill and knowledge, the section may apply. But beyond that, he submits, the section does not go. It does not cover the case where the specification just contains irrelevant material.

It follows says Mr Tappin that the Judge, in finding that 2 passages were not framed with reasonable skill and knowledge, was taking into account irrelevant matter. What matters for the purposes of the section is relevant skill and knowledge, that which is necessary to do the job of compliance with the EPC and providing accurate technical information. If there is some irrelevant but harmless matter left in the specification, the specification is nonetheless drafted with reasonable skill and knowledge. As Mr Tappin put it “it is enough if the patent agent has done his job.” I accept that submission. It makes no sense to hold that reasonable skill and knowledge should extend to matter which is irrelevant; as Mummery LJ put it in the course of argument: “reasonable skill and knowledge does not require an irrelevant degree of perfection.”

So it does not matter how much irrelevant matter is in, or left in by error in a conformity exercise. That is not to say that it is safe or sensible not to do a careful job of bringing a description into conformity with an amended claim. Failure to do so may well cause real difficulties in deciding on the meaning of the claim, which by Art. 69 is to be interpreted using the description and drawings. If that were so in a particular case, and the passages causing the difficulty were left in through negligence, then there would be a lack of relevant reasonable skill and knowledge.

But that is not this case – for it is accepted that the “offending” passages (whether as found by the Judge or on the extended basis as contended for by Mr Carr QC for Berry before us) could not mislead a skilled reader. The claims are clear despite the passages. That is why I also accept Mr Tappin’s submission that the dispute about the amount of irrelevant material is itself irrelevant. As he put it “nought plus nought equals nought".

I should mention what I regard as a desperate attempt to say that the passages are misleading. It was said that in the real world there are people who might read the patent, not know what claims are for, and think or at least wonder whether the patent covered solely turn-fit floor coverings. These notional readers are supposed to look at the drawings and read the text in some detail (so as to read the “offending” passages) but have no idea that the monopoly is defined by the claims. A distinguished patent agent, Mr Abnett, said that patent agents are consulted by people who have come across patents which might affect what they want to do and take advice. Such people, he opined, might look at this patent (perhaps obtained off the internet) and be caused to seek advice unnecessarily. I reject this as irrelevant. I suppose there will always be people who, through ignorance or incompetence, will misread or misunderstand patents (and a great many other things besides). But the law must ignore them.

I do not think any of the previous authorities have been concerned with a case such as this: one where there is no nexus between the reasons for the amendment and the alleged lack of reasonable skill and knowledge and where the patent with the alleged faults is not in any way misleading. The two main cases to which we were referred were Kirin Amgen’s Patent [2002] EWHC 471, [2002] RPC 43 (Neuberger J); [2002] EWCA Civ 1096, [2005] RPC 9 (CA) and Rediffusion Simulation v Link-Miles [1993] FSR 195.

Kirin-Amgen was a case involving a more serious error than that alleged here. Yet damages were not denied. There were statements in the patent that COS cells produced recombinant epo which had a higher molecular weight than urinary epo, that CHO cells produced recombinant epo which had a higher molecular weight than that produced by COS cells and there were different carbohydrate compositions for the urinary and the CHO cell produced epo. These were wrong but the only one found to result from a lack of reasonable skill and knowledge did not affect the actual grant of the claim which in due course was deleted by amendment. So there was no nexus between the amendment and the “offending” passages.

Neuberger J, upheld by this court, held that in the context of the specification as a whole, these errors did not amount to a lack of reasonable skill and knowledge. He said:

“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”.

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 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.”

Neuberger J was not concerned, as we are here, with an irrelevant alleged failure to exercise skill and knowledge. Nothing he said was concerned with such a case. But what I have said is entirely consistent with his approach. For he begins with the “importance of the specific passages”. If the specific passage has no importance whatever, then even if it is negligently wrong, s.63(2) is simply not engaged. There is no balancing exercise to be gone through.

Rediffusion was a first instance decision under the 1949 Act. As in this case an amendment was made during the course of prosecution to reduce the scope of the main claim. An attempt was made to make the specification conform to the amendment. But a blunder was made leading to a nonsense claim, one which had to be put right by amendment. There was a clear nexus between the reason for the amendment and the amendment. Not surprisingly, the blunder having being made by negligence, Aldous J held that the specification was not proved to have been drafted with reasonable skill and knowledge. Nothing in Rediffusion suggests that I would be wrong in holding that irrelevant blunders do not count.

Nor can I see any policy reason for coming to a different conclusion. We went into the history of the use of the phrase “reasonable skill and knowledge” both in this provision and in s.62(3). The requirement that a patentee proved his claim was framed in good faith and with reasonable skill and knowledge goes back a long way – to the first modern Act - the Patents, Designs and Trade Marks Act 1883, s.20. Here it appeared in respect to amendment. s.20 provided:

“Where an amendment by way of disclaimer, correction, or explanation, has been allowed under this Act, no damages shall be given in any action in respect of the use of the invention before the disclaimer, correction, or explanation, unless the patentee establishes to the satisfaction of the Court that his original claim was framed in good faith and with reasonable skill, and knowledge.”

Note that at that time the question related to the framing of the claim, not the specification. The provision was repeated in s.23 of the 1907 Act and then in s.59(3) of the 1949 Act.

Finally, in the 1977 Act, the provision changed so as to focus on the specification, not merely the claim. Neither side could offer any explanation as to why. It is possible that it was no more than a drafting change consequential upon the decision wholesale to use the word “invention” rather than “claim” throughout the Act.

In 1932 the requirement was imported into section 32A, introduced by amendment to the 1907 Act in 1919, which allowed relief to be given where only some claims were valid and infringed. A discretion was conferred in 1919. In 1932 the patentee was required to prove that his claim was “framed in good faith and with reasonable skill and knowledge” as a condition of granting relief. So in 1932 Parliament harmonised the condition for granting relief of a partially valid patent with the condition for awarding damages in respect of a patent which had been amended. Having said that, I do not see that that fact helps with the construction of the provision.

In the end therefore the history does not help. One can understand why as a matter of rational policy it might be that where a claim has required amendment, sloppy draftsmanship which led to the need to amend could be “punished” by depriving the patentee of an entitlement to damages prior to the amendment. But there seems no sensible reason to deprive a patentee of damages (and let an infringer off paying) merely because the patentee has some irrelevant harmless material in his specification. And all the more so where the facts are as in this case – the “offending” material remains in the specification after the amendment yet the patentee would clearly be entitled to damages for post amendment infringements. Any rational view of policy suggests that the provision should be construed so as to deprive the patentee of damages only where he has done something which might mislead. To that extent, therefore, I think policy supports the view I have taken.

Mr Carr suggested otherwise. He submitted that a patentee who has amended his patent should be regarded as the grantee of an indulgence. If, prior to amendment, he committed the past sin of framing the specification without reasonable skill and knowledge, he must be punished for that sin by depriving him of damages. And this punishment must be visited on him even though the fact that the patent needed amendment was not his fault. I reject this medieval view of the section.

Accordingly I have come to the clear view that the suggested faulty draftsmanship, whatever its scale, is simply not relevant to the “reasonable skill and knowledge” referred to in the section. It is not necessary therefore to say anything about Mr Carr’s attack on the Judge’s findings on the facts. I will, out of deference to the argument, do so, albeit briefly.

The main attack was on the turn-fit aspect of the specification, Mr Carr submitted that great swathes of the patent suggested that purely turn-fit joints were within the claimed invention. He focussed particularly on paragraphs 34-46. Now it is true that turn-fit joints are there described, but I think Mr Tappin provided the answer. The floor coverings are made of panels fitted together sidewise and lengthwise. The claims of the specification include the case where one pair of opposite sides is turn-fit whilst the other pair are snap-fit. So there is nothing inconsistent with the patentee describing turn-fit joints as such. Paragraph 34 begins with the words “According to the invention” before going to describe turn-fit. That must throw the reader back to the statement of invention at para. 13. This says that the invention is having the features of claim 1 – i.e. snap-fit. So I do not agree that the errors are extensive as suggested by Mr Carr.

I do however think that the Judge was right (in Para. 39) when he held that paragraph 45 does indicate that snap-fit is purely optional. A more perfect job of achieving conformity would have removed the words which suggested that was so. The Judge thought that in the context of the specification as a whole, that error did not amount to a lack of reasonable skill. I would not disagree – this is the sort of assessment with which an appeal court should not interfere unless it is plainly wrong.

As to the other error, about the invention extending beyond MDF/HDF, the Judge found that there was an error in paragraph 90 of the specification. Mr Carr pointed to a couple of other places where the same error was said to be repeated. I cannot think that matters even if he is right.

In the result I would dismiss this appeal. I would only add that it is probably time these provisions were reconsidered. It makes no sense, for instance, to restrict the right to damages but not the right to an account of profits (see Codex v Racal-Milgo [1983] RPC 369). Nor does it seem sensible to let a defendant off damages or an account unless he has actually relied upon something done by the patentee. Whether the provisions comply with the Directive on the Enforcement of Intellectual Property Rights 2004/48/EC is also a matter to be explored, but not here.

I agree.

I also agree.