England and Wales High Court (Patents Court) Decisions

B E T W E E N

This is the official judgment of the court and I direct that no further note or transcript be made

DATED: 29 April 1998

1. This is trial of an action for threats to which has been added an application for a declaration of non-infringement, a claim for revocation and a counterclaim for a declaration of infringement.

2. The plaintiff, Siegfried Demel, carries on business under the name Demotec Siegfried Demel in the manufacture and supply of bovine hoof care products. In particular the plaintiff manufactures and sells here and in other countries a product known as the "Easy Bloc" which is a prosthesis for alleviating certain types of lameness in cows.

3. The second defendant, Dr. Ernest Fergus Logan, is the registered proprietor of two United Kingdom patents, Nos. 2 223 152 and 2 257 611. The first defendant, C & H Jefferson is a firm of solicitors which has acted on behalf of Dr. Logan.

4. The manner in which this dispute has arisen is as follows. Dr. Logan’s patents cover prostheses of the same general type as the Easy Bloc. Dr. Logan’s prostheses are sold under the name "Cowslip". They have proved to be commercially successful. Dr. Logan learnt of the entry onto the market of the competing Easy Bloc product and discussed this development with C & H Jefferson. As a result from May 1997 onwards the latter firm sent a number of warning letters to various people, including two major customers of Mr. Demel. Those letters referred to both of Dr. Logan’s patents. Mr. Wyand QC, who has appeared on behalf of the defendants, does not dispute that those letters are threats and are actionable accordingly unless his clients can make out a case of justification.

5. The reaction of Mr. Demel’s customers to the receipt of these threatening letters was to remove the Easy Bloc from sale. When Mr. Demel discovered what had happened he consulted English solicitors. A certain amount of correspondence passed between the parties. By Writ dated 16 October 1997 the present proceedings were commenced. Mr. Demel not only seeks injunctive, declaratory and financial relief in respect of the threats but also a declaration of non-infringement both for the original Easy Bloc prosthesis and a slightly modified version of it. Nothing turns on the differences and in this judgment references to Easy Bloc should be understood as references to both versions unless the context otherwise requires. Mr. Demel also attacks the validity of Dr. Logan’s patents and seeks an order for revocation. The latter has already proved successful in part. Dr. Logan does not resist revocation of patent ‘611. It follows that the threats made in respect of that patent are not justified and Mr. Demel is entitled to relief in respect of them. The result is that this action has been concerned only with the validity and infringement of the ‘152 patent.

6. Dr. Logan was not happy at the prospect of being involved in proceedings in England. His operations are centered in Northern Ireland. On the basis of advice he received from C & H Jefferson, he decided that there would be tactical advantages if the issues of validity and infringement could be litigated before the High Court there. So, on 10 November 1997, he commenced patent infringement proceedings before the High Court in Northern Ireland. That action was based on the sale of some "8.00 worth of Easy Blocs by a customer of Mr. Demel in Northern Ireland. The existence of those proceedings led to a dispute which came before me earlier this year. In effect Dr. Logan wanted the English proceedings stayed pending the outcome of his "home" action. Mr. Demel wanted the reverse. I declined to stay the English action. I am not aware of what has happened in Northern Ireland but the action there has not come on for trial yet.

7. There is one other matter of history which should be recounted. At the end of July 1997 the lawyers acting on behalf of Mr. Demel asserted to Dr. Logan’s advisers that the patents were invalid, inter alia, on the ground that they contained added subject matter. Although Dr. Logan was and is not convinced that this criticism was justified, on the advice of his lawyers on 15 September he applied to the Comptroller to amend to delete certain passages in the patents and to make certain other minor amendments. That application was advertised on 16 November. Furthermore, in anticipation of an application being made to amend before the Court in the Northern Irish proceedings under section 75 of the Patents Act 1977, a further application was made to the Patent Office on 20 November for the amendments to be advertised as a pre-requisite to such proceedings. That advertisement was published on 17 December 1997. So the proposed amendments have been advertised twice.

8. Cows have cloven hoofs. Each hoof is made up of two claws separated by a narrow gap. Not infrequently one of those claws becomes damaged, for example by abrasion on concrete milking parlour floors, or infected. This is painful to the cow which becomes lame as a result. A lame cow is reluctant to walk so its browsing is reduced and this results in lower milk yield. Bovine lameness has been and continues to be a significant problem which has been recognised for a very long time. The great majority of lameness is caused by damage or infection of the medial claws on the rear hoofs. Over the years a number of strategies have been used to reduce the discomfort to the cow and, hopefully, to allow the damaged claw to heal. In one well established technique a wooden or rubber block is cut or shaped to fit on the bottom of the sound claw and is glued or nailed to it. This lifts the damaged claw away from the ground and results in it having to bear no or a significantly lessened load. Another technique directed particularly at curing infections of damaged claws is to use a complete plastic shoe into which the whole hoof, wrapped in bandages, is inserted. This product is sold under the name "Shoof". It is attached by draw strings around the ankle of the affected limb.

9. Mr. Logan’s device is very simple. He provides for a slipper made of plastics material with a thickened sole which fits onto the sound claw. In practice it is held in place by adhesive. It is designed to have the same effect as the prior art wooden and rubber blocks. This slipper is said to be very easy for even the most unskilled farmer to apply and gives almost immediate relief to the cow. As shown in the drawings attached to the specification, the slipper can have a small hole at the front which allows air and adhesive to escape as the cow’s claw is inserted into it. The way in which the slipper is attached to a cow’s claw is illustrated below:

Stage 1: The base of the sound claw is cleaned

Stage 2: Two part adhesive is poured into the slipper and mixed

Stage 6: The cow can now stand with the damaged claw raised off the ground.

10. As I have already mentioned, Mr. Demel's lawyers complained that the matter disclosed in the specification of '152 extends beyond that disclosed in the application as filed. Consequently they say that the unamended patent is invalid pursuant to the provisions of section 72(1)(d) of the Act. Although Dr. Logan does not accept that there is anything in the added matter attack, he has proposed certain amendments which would delete the material of which the plaintiff complains. Mr. Demel appears to accept that the amendments sought would cure most of the defects. However Mr. Campbell, who appears on behalf of Mr. Demel, argues that the court should not exercise its discretion in Dr. Logan's favour. The result of a refusal to allow amendment would be that if the patent does contain added matter it would have to be revoked. Of course, if the patent contains no added matter, refusing amendment will not result in the patent being invalid.

11. It is convenient to consider the issue of discretion first. The argument originally advanced on behalf of Mr. Demel was that there are four reasons for refusing the amendments namely; (1) Dr. Logan sought to obtain unfair advantage from the patent which he knew or should have known required amendment, (2) the amendment was not sought promptly, (3) the amendments are impermissible because they extend the scope of the protection and (4) there has been inadequate disclosure by Dr. Logan.

12. The last of these can be disposed of briefly. Under United Kingdom law it is necessary to give full disclosure in support of an application to amend. There is nothing in this case to suggest that Dr. Logan has failed in any material sense to comply with this requirement. In the end Mr. Campbell did not press this point.

13. The second objection, delay, was rightly abandoned in Mr. Campbell's reply speech. Far from there being delay, it appears that Dr. Logan took steps to amend his patent within weeks of notification of the plaintiff's objections. The proposed amendments have been advertised twice. The first advertisement was published more than a month before the commencement of the proceedings in Northern Ireland. The second was published only a month after commencement. It is difficult to see how Dr. Logan could have moved any faster. There is here nothing which Dr. Logan did or failed to do which would justify refusing him leave to amend.

14. In relation to the first objection, it was put to Dr. Logan during cross examination that he had deliberately chosen to sue a small trader in Northern Ireland, a Mr. Gilliland, in the hope of securing easy victory in litigation there without disclosing that the patent was invalid as Dr. Logan must have known. Furthermore it was put to him that the commencement of the proceedings in Northern Ireland were tactical and designed to steal jurisdiction from the Patent Court here in England. I fail to see how the latter point can have anything to do with the issue of amendment. Choosing forum is not a crime. It is a normal incident of multi-jurisdiction litigation. In this case Dr. Logan's attempt to divert the litigation into the High Court in Northern Ireland did not succeed. But in my view there was nothing improper in his attempt to do so. The heart of the criticism is directed at the decision to sue the small trader. In my view Dr. Logan's actions in this regard are not grounds for exercising the discretion against him. The suggestion is that Dr. Logan continued to rely on his patent when he knew it was invalid and used it to obtain an unfair commercial advantage. In effect he hid the invalidity from Mr. Gilliland.

15. First Dr. Logan gave evidence, which I accept, that he did not believe that the patent was invalid. His view was and is that it is valid. Even though his patent agents seem to have been persuaded by some of the added matter arguments, they advised him firmly that the patent was not incurably bad. Secondly there is no question of the defendants in the proceedings in Northern Ireland being kept in the dark as to the status of the patent. Although one of the defendants sued there was Mr. Gilliland, he was sued in relation to the sale of Mr. Demel's Easy Bloc product and Mr. Demel was sued at the same time in the same proceedings. Mr. Demel knew of the application to amend. Since the proceedings were directed at the Easy Bloc, it was entirely predictable that Mr. Demel and Mr. Gilliland would be represented by the same lawyers. They were. The proceedings in Northern Ireland were, in effect, directed at Mr. Demel. Further, in view of the fact that the application to amend had been advertised twice, it is not realistic to suggest that Dr. Logan was trying to hide any defects in his patent protection from either of those defendants. Again there is nothing here which would justify me in exercising my discretion so as to refuse amendment.

16. There was only one amendment in relation to which the third objection was advanced with any enthusiasm. Claim 1 of the patent, as proposed to be amended, reads as follows:

17. Claim 3 reads as follows:

18. Objection was taken to the proposed removal of the words in italics. It was said that this would extend the scope of protection in that the claim would now cover cases where the voids were filled other than at the time of fitting. However, even before the proposed amendment, such embodiments (assuming they are possible) were covered by the broader earlier claims. The amendment therefore does not extend protection and in my view is permissible.

19. It follows that I have come to the conclusion that there are no good grounds on which I should decline to allow the patentee to amend. As a consequence it is not strictly necessary to consider whether any of the allegations of added matter had substance. However, since this litigation may go further, it may be helpful if I set out briefly my views on this issue. There is no dispute now that claims 5, 6 and 8 all contain added matter. Dr. Logan is applying to delete those claims and since I have decided to give him leave to do so, those defects will be cured. However the major objections raised on behalf of Mr. Demel centered on Claims 1 and 4. By the time of his reply speech, Mr. Campbell had restricted those objections to three namely:

20. The first of these was by far the most important. What Mr. Demel says is that the application as filed does not state explicitly to which claw the slipper is to be fitted and that the skilled reader would understand that it was to be affixed to the diseased claw. It follows that the claims and consistory clause have the effect of disclosing something which was not present in the original application. Furthermore this addition, if it is one, is of major significance. According to the evidence before me, veterinary surgeons and farmers would only infrequently wish to attach a slipper to a diseased claw, if at all. If the patent is directed to slippers for that type of use, it would be directed at a very small minority of cases of lameness.

22. The construction of the application as filed and patent as granted is a matter for the judge. However, since he has to look at those documents through the eyes of a notional skilled addressee, the views of men in the art may be helpful although not determinative.

23. To support his case, Mr. Demel relied on the evidence of his expert, Professor Greenough, a highly regarded veterinary surgeon who has great experience of and has written about lameness in cows. Professor Greenough said that it was well known before the priority date of the patent that lameness could be reduced or eliminated by placing a block or lift under the sound claw. However he said that in his experience in about 5% of cases it was desirable to put the block or lift under the diseased claw and this was a procedure which he had used himself. He said that it was possible to read the application in a sense which indicated that it was directed at this 5% of cases. He explained by reference to certain passages in the specification how he came to this conclusion. He said that the application is concerned with what he calls a "new treatment" and is "not described as an improvement on the existing methods but appears to be put forward as being quite a different approach". He relied on the fact that the application says that the device is for protection. He said that "the assumption is simply that healing needs to take place in a protected environment" and the word "protection" carries with it the suggestion that the slipper is designed to protect, and therefore enclose, the damaged claw. By the time he came to give evidence, Professor Greenough accepted that there were certain passages in the application which appeared to be capable of being read as indicating that the slipper should be applied to the sound claw.

24. Quite the opposite view is expressed by Dr. Logan's expert, Mr. Blowey, also a highly respected veterinary surgeon. He says that the teaching of the application is to apply the slipper to the sound claw so as to raise the damaged claw off the ground and he sets out in his expert report how he comes to that conclusion. In the witness box he explained that, in his experience, applying a block or lift to a diseased claw was virtually unheard of. It would result in all the load of the animal being born by the diseased claw which would be the opposite of what was obvious and desirable.

25. By the time of his reply speech, Mr. Campbell's position was that although the majority of skilled addressees might well read the patent application in the way Mr. Blowey did, a minority would read it like Professor Greenough. The specification was therefore ambiguous and removal of that ambiguity amounted to adding matter to the specification.

26. I am quite unpersuaded by Professor Greenough's reading of the patent application. On its face it is directed at curing or alleviating the major causes of lameness, not a trivial minority as Professor Greenough suggests. The object of the invention is described as follows:

27. This suggests that what is being provided is a method of allowing the animal to load-up on all four limbs. This points strongly against making the diseased claw carry the cow's weight. That would be expected to increase the pain and lameness. Furthermore the application goes on to describe the existing methods of treatment including the use of wooden blocks and rubber pads. In both cases it states expressly that the prior art device is fixed to the healthy claw. It points out that one of the problems with the use of rubber pads is that they are nailed to the sound claw and this sometimes results in extensive damage to that claw. The invention is then put forward as a quick and effective procedure "in the treatment of lame dairy cows" which employs an "innovative device" in the form of a plastic surgical slipper. None of this suggests that the treatment is directed to the minority of lameness cases. Nor does it suggest that the procedure to be used is fundamentally different to that used in the prior art. It is the device employed which is different. In particular it is shaped to allow different means of attachment. After the description of the preferred embodiment, which refers to adjusting the thickness of the base of the slipper, the application concludes with the following paragraph:

28. The slipper is designed to assist the cow to return to fully loaded four leg walking as soon as possible. This is what the prior art blocks and pads did by removing the damaged claw from load bearing. It is extremely difficult to see how applying the slipper to the damaged claw could achieve the advantages set out in this paragraph.

29. It appears to me that the natural meaning of the application to a man skilled in the art is that the slipper is to be attached to the sound claw. That is what it implicitly, but clearly, discloses. In the end I think that Professor Greenough accepted this as well. He accepted that the application was directed more at a practising veterinary surgeon like Mr. Blowey than someone who was now more interested in the academic side, as he was. He also conceded that some passages in the application pointed away from his construction. Further it became apparent that in determining the meaning of the document the Professor had adopted a "literal" rather than common sense approach. He said:

30. Even adopting an extremely literal approach, I do not accept Professor Greenough's construction. But in any event it is the common sense approach which should be adopted. This added matter attack fails.

32. The attack based on Claim 4 is also bad. The form of claim to which Mr. Demel objects is as follows:

33. In the proposed amendment, so far as relevant to this issue, the words "one or more ooze holes" is to be replaced by "an ooze hole". Mr. Campbell accepts that Dr. Logan has always been entitled to a claim in the latter form. Such a claim reads on to what was described in the application. He accepts that such a claim would be infringed by slippers with one or more ooze holes. It follows that the wording "one or more ooze holes" in the original form of claim 4 adds nothing by way of protection. I think Mr. Campbell accepts this also. It is very difficult to see how the use of these words adds anything at all to the application as filed. They merely say in long form what was implicit throughout.

34. I can therefore turn to the question of validity. As has been mentioned earlier in this judgement, there are a variety of prior art devices and methods which have been used to treat damaged hoofs. By far and away the most common was the wooden block. This has been used for some decades. It is still used in some circumstances and by some veterinary surgeons although it appears that sales of wood blocks are now being replaced by sales of the Cowslip and Easy Bloc. The way in which wooden blocks are attached to sound claws is illustrated below.

35. The wooden block is fixed to the underside of the sound claw by glue. From the rear the appearance is as follows:

36. From the side, the hoof with block attached looks like this:

37. The blocks themselves are frequently made oversize and need to be cut or trimmed on site to fit as closely as possible to the underside of the claw. From the underside a wood block appears as set out below. The figure illustrates how a large slip may be removed from the block to reduce its overall size:

38. Although these devices have been used for a very long time, getting them to fit properly is a skilled task. The cow has to be restrained in a crush and the affected leg is tied up so that the veterinary surgeon can gain access to the underside of the hoof. The block is then cut to size as well as the skill of the surgeon will permit. It is then stuck to the cleaned underside of the sound claw. The glue takes about 10 to 15 minutes to set. There was no dispute between the experts that this is a skilled operation. If the wood block is not cut to size properly it may stick out from under the claw. There is then an enhanced risk of the wooden block being caught under a protruding object and being wrenched off the claw. Furthermore it is fairly difficult to retain the block in position during the curing time of the adhesive. The cow is likely to be restive and the block will tend to slide about on the underside of the claw. The surgeon will have to continue to manipulate the block to try to ensure that it is kept in more or less the right position. He will frequently end up with his hands covered with adhesive. If the block is not put on correctly it will wear badly and may need to be replaced prematurely. The difficulty in fitting blocks was expressed pithily by Professor Greenough:

39. There was no dispute between the experts that the Cowslip and the Easy Bloc are much easier to fit. They employ quick setting glue and because they are shaped to accommodate the claw, they are much easier to retain in position during the setting process. They are so much easier in fact that they are now used by many farmers without the need to call in the veterinary surgeon. Furthermore the skimming of the adhesive on the Cowslip and Easy Bloc as illustrated at Stage 3 above makes it much less likely that there will be a protruding lip. The chances of the slipper being wrenched off is therefore lessened.

40. The similarity between the Cowslip/Easy Bloc slipper and the wooden block is immediately apparent. They perform the same function in essentially the same way. However the plaintiff does not suggest that the patented device is obvious over this prior art. He only suggests obviousness over the Shoof product to which I have referred briefly at the beginning of this judgment.

41. The Shoof is a plastic shoe which encloses a complete hoof. No doubt this is the derivation of its name. When put on the hoof it looks like this:

42. The purpose of the device is explained in its advertising leaflet Bundle 3 Tab 9.. The damaged claw is cleaned and then dressed with an antibiotic. The whole hoof is then wrapped in a bandage. The bandaged hoof is then tied into the Shoof. The effect of the latter device is therefore to keep the antibiotic impregnated bandage in place on the hoof. It ensures that the damaged claw continues to be exposed to antibiotic. The leaflet emphasises this purpose and notes that the product reduces antibiotic usage. Antibiotic treatment does not need to be repeated regularly because the bandage keeps the antibiotic in contact with the damaged claw. Furthermore the Shoof can be reused by cutting the string and using a refill kit which is sold by the manufacturers. That consists of tie string, sachet of antibiotic and a bandage. The leaflet explains that the use of such a kit is "essential" for successful reuse of the Shoof. In fact the sachet of antibiotic is placed inside the Shoof and the leaflet explains that this "bursts when the animal walks giving a footbath effect". In its standard configuration, the Shoof has a single elevation across its width. In other words it does nothing to shift the support onto the sound claw and away from the damaged one. However there are non-standard Shoofs which have elevations on the underside on one side or the other. These are designed for cases where the bad claw is more seriously affected. In these devices the complete hoof is still slipped inside and rests on a substantially flat plastics floor but the floor itself is only supported underneath on one side. The floor on the unsupported side will tend to flex a bit under the weight of the cow. This means that there can be some diminution of the loading on the claw on the unsupported side.

43. As I have said, the only argument of invalidity advanced is based on this piece of prior art which was available for at least 5 years before the priority date of the patent. The case advanced is that it would be obvious to cut the Shoof in half vertically from front to back and to seal up the open side so created. Such a half-Shoof would look very much like the Cowslip or Easy Bloc and could be used in the same way. Such a small modification must be obvious.

44. In my view this argument fails. None of the evidence supports it. Mr. Blowey's evidence was that the Shoof was a bad product which was very difficult to use. He hardly ever used it himself. He would not have thought of modifying as suggested by the plaintiff. Perhaps more telling is the evidence of Professor Greenough. He had used the Shoof and produced a half-Shoof which he had made for the purpose of the trial. He explained that he made it to show just how easy it would be to make something falling within the claims of the patent out of that product. However he readily agreed that he never thought of cutting the Shoof in half until he had seen the Cowslip, the Easy Bloc and the patent in suit. He accepted that it was not something he would have been likely to think of and he did not think other veterinary surgeons would think of it either.

45. Furthermore it appears to me that to cut the Shoof in half, as suggested, would be counter-intuitive. The primary purpose of the Shoof is to help to retain a medicated bandage in place on the damaged claw. If it is cut in half and used only on the sound claw, like the Cowslip and Easy Bloc, it would cease to serve that purpose entirely. It would be incapable of playing any part in retaining the bandage in place. The fact that the patented device and the Shoof have some physical resemblances should not be allowed to hide the fact that they perform quite different functions. The ease with which one can be modified to look like the other says little about whether that modification is obvious. It may well be inventive to realise that a new and effective product can be made by a simple change to a product readily at hand.

46. Furthermore, the history of the treatment of lameness of cows supports Dr. Logan's case. In the end there was no dispute that prior to the patent the difficulty associated with trying to fix wooden blocks on claws was significant and represented a problem which veterinary surgeons would prefer to avoid. In his written report Professor Greenough denied that there was any problem but he readily retracted that when giving oral evidence. He accepted that what was needed was something which was easier to apply than the wood blocks. For example he said:

47. Further he eventually expressed the view that this was indeed a worthwhile invention. He said:

48. He went on to explain that the reason he was opposed to the patent was because he thought it undesirable that a monopoly should be allowed to exist which might stand in the way of further development in this field. These sentiments may be laudable but they have nothing to do with whether the invention is obvious.

49. Similarly Mr. Blowey said that he wished he had thought of the Cowslip for himself. He had thought about the issue long and hard and had come to the conclusion that it was not the obvious thing to do. He was clearly alert to the fact that the Cowslip could be regarded, with hindsight, as only a small step forward from the use of wood blocks. But he was convinced that the idea was not obvious. His view of the Cowslip was that it was that they were a "massive step forward" compared with wood and rubber blocks.

50. In all of this evidence the experts were considering whether it was obvious to go from the wooden block to the Cowslip. As noted already, this is not the starting point pleaded by the plaintiff. However the evidence is still relevant. If any step was obvious, it seems to me it would have been the step from wooden block to Cowslip. The fact that decades had passed without the problems being solved points away from obviousness. The Cowslip is easy to construct and could have been designed and manufactured at any time over the decades since the introduction of wood blocks. It was not. The Shoof is further away in concept. The fact that it was not obvious to go from wooden blocks to the Cowslip reinforces the view which I have expressed above that the Shoof does not render this invention obvious.

51. The invalidity attack fails accordingly. In coming to this conclusion it has not been necessary to consider the argument of commercial success advanced on Dr. Logan's behalf. Nor is it necessary to consider the evidential value of the fact that the Cowslip has received 4 technical awards or medals in three countries.

52. The only other issues of significance are arguments of non-infringement advanced on behalf of Mr. Demel. The first relates to claim 1. That can only be infringed by plastic slippers which are "tailored" to increase the depth of the sole of the sound claw so that the non-slippered diseased claw is removed from contact with the ground. It is argued that this requires a bespoke operation in which the slipper is custom-shaped to each individual claw on site. Since the Easy Bloc is pre-formed in a shape which will accommodate most medial claws, it does not infringe.

53. In my view this involves a misreading of the claim. When the claim refers to the slipper being tailored to achieve a particular purpose it means no more than that the slipper is shaped or designed for that purpose. A suit is no less tailored because it is made available as a ready to wear item. The same approach applies here.

54. The other argument of non-infringement relates to claim 3. This is set out above. It provides that "air voids" between the internal slipper surface and the claw surface are filled with the adhesive. It is said that this is not infringed because the cement is mixed inside the Easy Bloc and therefore there are no air voids to fill. I can not accept this argument either. The claim has to be read sensibly. All that it means is that the space between the internal slipper surface and the claw surface is filled with cement. Absent the cement, the area would be filled with air. Construed in this manner, the Easy Bloc in use infringes this claim as well.

55. It follows that for the reasons set out above, the defendants have made out the case of justification in relation to the '152 patent. That patent is valid and infringed by the Easy Bloc.