Icescape Ltd v Ice-World International BV & Anor

This is an action for an injunction and damages arising out of alleged threats of patent infringement. It is admitted that threats were made but contended that (a) they were justified and (b) in any event the Defendants have a defence under section 72 of the Patents Act 1977. There is also a claim for a declaration of noninfringement, for an order that the patent be revoked and a counterclaim for infringement.

With respect to the attack on the patent, it is common ground that the patent is invalid (because of prior use) unless it can maintain its earliest priority date and valid if it can maintain that date. Infringement is in dispute.

The invention in the patent in suit (the P), EP(UK) 1462755 B1, is for a cooling member for a mobile ice rink, that is to say an ice rink which is erected for a temporary period before being packaged up and transported to another location.

The general nature of the invention and the prior art system and its disadvantages are described in the first three paragraphs of the P as follows:

The invention relates to a cooling member for a mobile ice rink provided with:

a feed manifold extending in a transverse direction and a discharge manifold, and

a number of longitudinal pipes which extend transversely to the manifolds and can be connected at a first end to a manifold, two longitudinal pipes in each case being in fluid communication with one another at a second end via a connector, so that a fluid path is formed from the feed manifold to the discharge manifold via the two connected longitudinal pipes.

The object of the invention of the P is set out in paragraph 4:

the cooling member comprises at least two elements (41, 42), each with a feed manifold (43,45) and discharge manifold (44, 46) and a number of longitudinal pipes (50, 51) connected thereto,

wherein each longitudinal pipe comprises at least two rigid pipe sections (3, 12, 16, 24, 68, 69) that are connected to one another via a joint member (4, 13, 17, 25, 70, 132, 133) such that they are fluid-tight, and

wherein by moving the joint members (4, 13, 17, 25, 70, 132, 133) a first series of parallel pipe sections (68, 68', 68") can be placed in a transport position with respect to a second series of parallel pipe sections (69, 69', 69") connected thereto, in which transport position the two series of pipe sections (68, 68', 68"; 69, 69', 69") are at an angle with respect to one another or are positioned on top of one another, and can be placed in an operational position in which the two series of pipe sections (68, 68', 68"; 69, 69', 69") extend in the extension of one another,

wherein the first and the second element (41, 42) can be placed in the operational position alongside one another such that the feed and discharge manifolds (43, 44, 45, 46) of the elements extend in the extension of one another in the transverse direction,

wherein the feed and discharge manifolds of the two elements are provided with a coupling member (47, 48) to make a fluid-tight connection between the respective feed and discharge manifolds of the first and the second element.

The pre-characterising part of the claim describes the prior art systems wherein the feed and discharge manifolds extend in one direction and the longitudinal pipes are perpendicular thereto thus providing a basically rectangular array of cooling pipes. Pipes and manifolds suitable for mobile ice rinks are typically 6 metres in length or less and if longer lengths are required these can be made by joining together individual lengths using conventional coupling means.

In the characterising part, A introduces the concept of elements and provides that there are at least two, each of which has a feed and discharge manifold and a number of longitudinal pipes connected thereto; B provides that the longitudinal pipes are made up of a number (of at least two) rigid pipe sections joined together by a fluid tight joint member; C provides for the joint member being such that the pipe sections can move relative to each other, the idea being that the pipe sections can be folded over each other and placed on a truck in a ‘transport position’ or laid end to end in an ‘operational position’ when creating a rink; D provides for the elements to be laid next to each other so that the feed and discharge manifolds are in series, extending in a direction transverse to the longitudinal pipes; finally, E provides for a coupling member for the feed and discharge manifolds of the elements so as to provide for a fluid-tight connection between the respective feed and discharge manifolds of the first and second elements.

A schematic of a system in accordance with the invention is annexed hereto as Figure 1 (Fig 8 of the P). In the diagram, item 72 is a cooler and 71 a reservoir, 41 is a first element and 42 a second element of feature A of the claim, 43, 45 and 44, 46 are the feed and discharge manifolds of the two elements, 53 and 54 are the longitudinal pipes of feature B, 70 is the flexible joint member of feature C and 47 and 48 are the coupling members of feature E of the claim.

Also annexed hereto as Figure 2 (Fig 7 of the P) is a schematic which shows a series of assemblies (23) of two parallel pipes made up of rigid pipe sections 24 connected together by flexible joint members (25) and transverse connectors (27), the feed and discharge means being provided by two collectors/manifolds (in 28). Item 30 is a cooler, 29 a pump and 22 the housing for the water of the rink.

It is evident from the description in the P that the base of an ice rink can be made up, depending on its size, by a number of elements connected together to give the requisite width in one direction and a number of longitudinal pipes connected together to give the requisite length in a perpendicular direction.

Both parties adduced witness evidence of fact but none of the witnesses were required to attend for cross examination.

As for expert evidence, the Claimant relied on a Mr Nelson and the Defendant a Dr Pearson.

Mr Nelson has worked in the ice rink industry since 1998 and he considers himself to be one of the UK’s leading authorities in modern ice rink design and construction as well as being very familiar with the many different cooling floor systems which are used to build temporary ice rinks. I found him to be a practically minded and helpful witness with no particular axe to grind. I am satisfied that he understood his responsibilities and was doing his best to assist the court.

Dr Pearson is a chartered engineer with 30 years’ experience in the refrigeration business. He has double first class degrees of BSc and BEng and a PhD in Mechanical Engineering. He has particular experience in the design manufacture and installation of chiller systems and has worked on numerous products for ice rinks including both permanent and temporary installations. Dr Pearson was subject to aggressive questioning which revealed that he was an intelligent and precise witness. I am satisfied that he was trying to assist the court but on occasion he was prone to advocate the position the Defendants sought to adopt. Moreover he gave quite a lot of evidence about whether or not the P was entitled to its earliest priority date, much of which was not only inadmissible but was based on an incorrect understanding of what was required to give priority and an incorrect appreciation of the content of the claims. As such, it was not helpful.

There was scarcely a dispute about the identity of the skilled addressee, the person to whom the P is addressed. In my judgment the P is addressed to a person with an engineering background familiar with cooling technology/refrigeration technology and interested in the design, construction and supply of temporary/mobile ice rinks.

Much of the common general knowledge was agreed and, so far as is relevant, I find it to include the following:

With respect to the members which join two sections of longitudinal pipe, Mr Nelson’s evidence was that both rigid and flexible joining members were well known. During the early part of his cross examination Dr Pearson agreed with this but later he said that he did not know about the use of such flexible members. I prefer Mr Nelson’s evidence on this topic and am satisfied that the use of flexible coupling members for joining lengths of longitudinal pipes was well known. However, there was no evidence that such members were sufficiently flexible to permit one length of pipe to flex significantly in relation to an adjacent pipe so that one length could fold back over another.

There was no dispute about the approach. The general position was summarised by Jacob LJ in Virgin Atlantic v Premium Aircraft[2009] EWCA Civ 1062, [5]:

The first overarching principle is that contained in Article 69 of the European Patent Convention;

Article 69 says that the extent of protection is determined by the claims. It goes on to say that the description and drawings shall be used to interpret the claims. In short the claims are

It follows that the claims are to be construed purposively—the inventor's purpose being ascertained from the description and drawings.

It further follows that the claims must not be construed as if they stood alone—the drawings and description only being used to resolve any ambiguity. Purpose is vital to the construction of claims.

When ascertaining the inventor's purpose, it must be remembered that he may have several purposes depending on the level of generality of his invention. Typically, for instance, an inventor may have one, generally more than one, specific embodiment as well as a generalised concept. But there is no presumption that the patentee necessarily intended the widest possible meaning consistent with his purpose be given to the words that he used: purpose and meaning are different.

Thus purpose is not the be-all and end-all. One is still at the end of the day concerned with the meaning of the language used. Hence the other extreme of the Protocol—a mere guideline—-is also ruled out by Article 69 itself. It is the terms of the claims which delineate the patentee's territory.

It follows that if the patentee has included what is obviously a deliberate limitation in his claims, it must have a meaning. One cannot disregard obviously intentional elements.

(vii) It also follows that where a patentee has used a word or phrase which, acontextually, might have a particular meaning (narrow or wide) it does not necessarily have that meaning in context.

It further follows that there is no general “doctrine of equivalents.”

On the other hand purposive construction can lead to the conclusion that a technically trivial or minor difference between an element of a claim and the corresponding element of the alleged infringement nonetheless falls within the meaning of the element when read purposively. This is not because there is a doctrine of equivalents: it is because that is the fair way to read the claim in context.

Finally purposive construction leads one to eschew the kind of meticulous verbal analysis which lawyers are too often tempted by their training to indulge.

That case went on to deal with three further matters which related to and involved the question of how much of the law and practice of the patent system the skilled addressee is taken to know and take into account when he is trying to work out what, by the words of the claim, the patentee was intending to convey. The Court concluded that the skilled addressee was to assume that the claim was for the purpose of defining the monopoly and that it should be for something new. He was also taken to be aware of drafting conventions, the meaning of divisional applications and the like and the fact that identifying numerals in a claim do not influence the construction of a claim.

There are some construction issues in this case but it will be convenient to deal with them in the context in which they arise. Out of context they do not have much interest. Neither party contended that any of the terms in the patent were terms of art.

The first matter to consider is whether or not the P is entitled to rely on the Priority Document (the PD) for priority.

The approach to assessing priority was set out by the Court of Appeal, per Kitchin LJ, in Medimmune v Novartis[2012] EWCA Civ 1234 [151] - [154]:

In HTC v Gemalto[2015] RPC 17, Floyd LJ (with whom Vos and Laws LJJ agreed) cited the above passage from Medimmune and added as follows:

Thus the issue is one of technical disclosure. In Samsung v Apple[2013] EWHC 467 (Pat), [130], Floyd J gave an example which illustrates when a specific and limited disclosure in a priority document could provide support for a wider claim:

The invention in the PD is for a mobile heat exchanger and system for providing a skating rink provided with such a heat exchanger. The general nature of the invention and the prior art system and its disadvantages are described in the first few paragraphs as follows:

The PD goes on to describe various preferred embodiments and claims 1 and 9 are in these terms:

at least two generally rigid pipes for transport of a first medium, and

coupling element which interconnects the two pipes, and

Thus the express disclosure of the PD is that the heat exchanger of the invention can vary in size by varying the number of assemblies used. An example of a structure in accordance with claim 9 is in Fig 6 of the PD (it is the same as that shown in Fig 7 of the P, annexed hereto as Figure 2).

Mr Campbell QC, for the Claimant (Icescape) submitted that the striking difference between the disclosure in the P and that in the PD is that the P describes a cooling member in which there are at least two elements (feature A of the claim) placed in position alongside each other in a particular orientation (feature D of the claim) wherein the manifolds of the two elements are provided with a coupling member which makes a fluid-tight connection between the respective feed and discharge manifolds (feature E of the claim) whereas the PD is wholly silent in these respects; and instead refers merely to a heat exchanger with a number of assemblies oriented one with respect to the other in a substantially parallel manner.

Mr Platts-Mills QC, for the Defendants (Ice-World), acknowledged that, as a matter of the actual words used, there was no express disclosure in the PD of ‘elements’ and the way they were connected together, but submitted that such were nevertheless disclosed since the skilled addressee, reading the PD, would understand these features to be present in any ice rink made using the heat exchangers of the PD.

The heart of Mr Platts-Mills’ argument was the submission that a patent specification or a priority document is deemed to incorporate, and therefore disclose, all the common general knowledge in the relevant art. This was not a proposition with which I was familiar and no authority was cited in support. Mr Platts-Mills submitted that it was a consequence of and flowed directly from the proposition that a patent must be interpreted through the eyes of a skilled addressee and not an equity lawyer.

Mr Platts-Mills referred to this passage in the PD which describes how an ice rink of substantial dimensions (say 20m by 30m) can be constructed:

Mr Platts-Mills submitted, rightly, that the first of these two paragraphs describes how ice rinks of significant length can be constructed and the second describes how ice rinks of significant width can be constructed. Mr Platts-Mills then turns to his submission in paragraph 30 above.

The argument runs as follows. Mr Platts-Mills submitted that the skilled addressee would approach the PD and see that it was concerned with mobile ice rinks and therefor have in mind (as a result, implicitly, of being told of) the mobile ice rinks which formed part of the common general knowledge, i.e. a construction in accordance with Fig 8 of the P, (Figure 1 attached hereto), (in particular, with features A, D and E of claim 1, being those features Mr Campbell submitted were not disclosed by the PD) save that the coupling members 70 were rigid rather than flexible). Thus, he submitted, the skilled addressee would read the PD, including its Fig 6 (Figure 2 attached hereto) with its flexible coupling elements 25 (they are called joint members in the P), and realise that he was being told about the use of those flexible coupling elements in the system which he had in mind. Accordingly, he submitted, the skilled addressee was able to derive the subject matter of claim 1 of the P directly and unambiguously from the disclosure of the PD.

Recognising that this argument might get him home on priority but not on infringement, Mr Platts-Mills prayed in aid Floyd J’s example of the ‘nail’ in Samsung. He submitted that the ‘coupling member’ of feature E of the claim (implicitly disclosed by the PD since it was a feature of the common general knowledge mobile ice rink) was in the same class as the ‘nail’ in Samsung and that, as a matter of construction, the expression should be interpreted as ‘coupling means’. So, since ‘nail’ in a PD might provide support for ‘fixing means’ in a P, so ‘coupling member’ (implicit in the PD but explicit in the P) should be construed as ‘coupling means’ in the P.

That, as I understand it, was the argument Mr Campbell was dismissive of it. He submitted that it confused disclosure of a document with what that document might lead a skilled addressee to do or prompt him to think of - relying on HTC v Gemalto and the cases cited above in the extract from Medimmune.

In my judgment Mr Campbell’s analysis is the correct one. In the context of priority, the court assumes the mantle of the skilled addressee (with his common general knowledge) to interpret and understand the PD to see whether it supports the invention in the P, to see whether it gives him essentially the same information as in the claim of the P and enables him to work that invention.

Thus, if a priority document describes the use of a nail to fix two things together in circumstances where it is evident that a screw or glue or any other such would do then the word ‘nail’ may provide support for ‘fixing means’ in the claim of a patent. That is how I understand Floyd J’s example in Samsung.

But if the skilled addressee reads a priority document and says to himself ‘Oh, I know how that can be used, it can be used for X’, then he is doing more than interpreting the document. He is adding to the disclosure and deciding that it can be used for X. A patent for X would not be entitled to claim priority from the earlier document.

Thus, I reject the submission that a priority document implicitly incorporates, and therefore discloses, all the common general knowledge in the art. The skilled addressee brings his common general knowledge to bear when he interprets a priority document or a patent; he is not taught that information by those documents.

Secondly, Mr Platts-Mills’ use of the Samsung nail is not permissible. Floyd J was giving an example of how a term in a priority document, ‘nail’, might provide support for another, broader term, ‘fixing means’ in the claim of a patent; he was not concerned with how the term ‘nail’ might be construed if it were used in such a claim. Support and construction are completely different concepts.

In my judgment the invention of claim 1 of the P is not supported by matter disclosed in the PD; the PD does not contain essentially the same information as that in the P or in claim 1 of the P, it merely contains information which may prompt the skilled addressee to use it in accordance with the claim of the P.

Accordingly the priority of the P is its filing date and not earlier. Since invalidity is conceded if the P is not entitled to the priority date of the PD, the P must be revoked.

Icescapc accepted that its mobile ice rink product incorporated all of the features of claim 1 of the P save for features D and E and in particular the “coupling member to make a fluid-tight connection between the respective feed and discharge manifolds of the first and the second element”. This raised the first issue of construction and since neither party contended there were any particular terms of art, the matter is for the court and not the witnesses. Nevertheless Dr Pearson gave his view. He accepted that there was no coupling between the respective manifolds of Icescape’s device but contended they were connected by a coupling member. To get close to understanding this apparent contradiction in terms it is necessary to see how the Icescape system works.

Icescape provided a product description and drawings to explain its system, some of which are annexed hereto for convenience. Turning first to the schematic which shows coolant flow through the system (Figure 3 hereto), this comprises two diagrams, the upper shows the flow in plan view and the lower in sequential view. The feed flow is blue and the discharge flow is maroon/brown and the system comprises three elements (loosely the same as the elements of claim 1 of the P), El, E2, E3. Coolant enters the system from the right hand side through pipe P (which acts as a balancing line) and flows into feed manifold FI with end member BF providing a stop. From FI the coolant flows through F2 of each element to secondary manifold F3 whereafter it passes through a number of parallel longitudinal pipes C to a return manifold (coloured orange at the bottom of each element) after which it becomes discharge flow, passes down pipe C to discharge manifold D3 and pipe D2 to discharge manifold D1 and then back to the chiller/pump, X.

Figure 4 hereto shows the secondary manifold in partial cross section. It comprises a collector/manifold H with two compartments, F3 and D3. Coolant enters via IF (from F2) into F3 and passes to the longitudinal pipes C through feed outlets OF. Returning flow enters H via discharge inlets ID to D3 and out discharge outlet OD to D2 and then on to D1 and the chiller.

Figure 5 hereto shows three secondary manifolds next to each other (each comprising F3 and D3) with feed pipes F1 and F2 and discharge pipes D2 and Dl. Each secondary manifold system is labelled El, E2, E3 respectively and the longitudinal pipes are C.

There are joint members along the length of the longitudinal pipes which permit the parallel pipe sections to be moved in relation to each other and placed in either a transport position or an operational position, as in feature C of claim 1 of the P.

It can be seen that the design of Icescape’s system is somewhat different from that shown in Fig 8 of the P (Figure 1 hereto). Icescape accepts that its system has ‘elements’ (El, E2, E3 etc) but contends that features D and E of claim 1 are missing. Icescape contends that feature D requires a series connection of the two elements such that coolant flow passes through the feed manifold of one on its way to the feed manifold of the next, and that this flow is through the coupling member of feature E.

In his report Dr Pearson asserted that the Icescape design infringed claim 1 of the P and he produced diagrams (reproduced at Figure 6 hereto) extracted from the fluid flow schematic at Figure 3 hereto which he contended showed the network of pipes which comprised what he termed the ‘feed coupling member’ and ‘discharge coupling member’, and he said that these two together made up the ‘coupling member’ of the claim. As part of his analysis he noted that the claim simply requires there to be a “connection between” the manifolds. I asked him why he had put the words “connection between” in inverted commas and his response was that he presumed it was because these words were used in the claim; he apologised if he was mistaken. He was mistaken.

Moreover, it is clear from his report that Dr Pearson considered that all that was required for this part of the claim was piping which joined together the feed and discharge manifolds in a fluid tight manner. His reasoning appeared to be based on a mistaken appreciation of the content of the claim and an observation that otherwise the system would not work. It seemed to me to be a good example of why the courts have repeatedly said that experts should not give evidence about the meaning of claims which do not use terms of art or otherwise require some explanation because of their subject matter.

I asked Mr Platts-Mills to identify what in Icescape’s system did he contend was the ‘coupling member’ of feature E of the claim. He responded with a coloured mark up of a drawing from the product description (Figure 5 hereto). He submitted that the purpose of the coupling member was to enable the plumbing of the system to provide coolant to each pipe in a similar condition, i.e. at about the same temperature, and that this purpose was unrelated to physical geography.

Mr Platts-Mills identified the route taken between Element 1 (El) and Element 2 (E2) comprising El’s F2, part of F1, E2’s F2, and El’s D2, part of D1 and E2’s D2. He submitted that the components comprising that route were a coupling element (marked yellow in the attached Figure 5), alternatively that they did so in conjunction with the joint member marked in red on Figure 5. One problem with this route is that it is not one along which coolant flows. The F2s and D2s run in parallel not in series.

Alternatively, Mr Platts-Mills submitted that the joint members between F2 and F3 and between D2 and D3 (marked red in the attached Figure 5) alone were coupling members.

Alternatively, Mr Platts-Mills also referred to the fact that pipes F1 and D1 are delivered to site in about 8m lengths and are welded together to create a sufficiently long F1, D1 for the ice rink in question. He submitted that the welds on these lengths were ‘coupling members’ of the claim since they connected lengths of manifolds to each other.

It is clear from Mr Platts-Mills’ submissions that he is adopting the approach of Dr Pearson, that if there is fluid connection in the system such that the device works, there is a coupling member joining the manifolds and features D and E of the claim are satisfied.

Mr Campbell was dismissive of Mr Platts-Mills’ argument. He submitted that it ignored the language of the claim and addressed purposive construction at the wrong level of generalisation. He submitted that the claim should be read as a whole and that features D and E in particular should be read together. Thus feature D provided the means whereby the cooling member can extend in a direction perpendicular to the longitudinal pipes, and it did so by providing that the elements of feature A are placed end to end such that the feed and discharge manifolds of those elements lay next to and in series with one another. He submitted that feature E taught that the feed and discharge manifolds of each element were provided with a coupling member so that adjacent feed manifolds and adjacent discharge manifolds could be joined together in series. He submitted that a coupling member was just that - an item or member whose function and purpose was to join together the manifolds of adjacent elements and thereby enable the extension of the cooling member along the direction of the axis of the manifolds (being perpendicular to that of the longitudinal pipes) with coolant flowing from one element to another via the coupling member. He submitted that the Icescape device simply did not have these features.

With respect to the suggestion that the welds of F1 were coupling members, Mr Campbell submitted that such was an abuse of language since F1 was a continuous pipe not capable of being uncoupled. He submitted that the red couplings in Figure 5 hereto were provided only on the manifolds of one element and that the argument was not improved by adding the yellow pipes to the red coupling, the reason being that coolant did not flow from one element to the next via this route; any coolant passing down any F2 went through the longitudinal pipes and out the discharge manifold rather than to the feed manifold of an adjacent element.

In my judgment Mr Campbell's analysis is the right one. It is not permissible to ignore the language of the claim and replace feature E with either nothing at all (since it is implicit that the pipe work will be connected up so that coolant flows into and out of the cooling member on its way from and to the chiller) or with language such as “wherein the feed and discharge manifolds of the two elements are connected into the system in some leak-free manner”, which is, effectively, Dr Pearson’s and Ice-World’s construction.

Accordingly, in my judgment the case on infringement fails and the application for a declaration of non-infringement succeeds.

I next turn to relief and deal with whether or not Ice-World has a defence to the claim for relief under section 70(2A) of the Act in case I am wrong about any of the other matters. This defence was pleaded but the pleading was not supported by any particulars setting out why or how it was made good. The sub-section, in its amended form, is in these terms:

the claimant or pursuer shall be entitled to the relief claimed only if he shows that the patent alleged to be infringed is invalid in a relevant respect;

even if the claimant or pursuer does show that the patent is invalid in a relevant respect, he shall not be entitled to the relief claimed if the defendant or defender proves that at the time of making the threats he did not know, and had no reason to suspect, that the patent was invalid in that respect.”

Apparently there is little judicial authority on the proper interpretation of this section, my attention being drawn only to the Court of Appeal’s judgment in Sudarshan v Clariant[2103] EWCA Civ 919. The issue in that case was whether the knowledge of a patent agent who sent a threatening letter and who had, himself, no reason to know or suspect that the patent was invalid was the knowledge which should be attributed to the company. At [132] Kitchin LJ said this:

The approach to be adopted in deciding whether the knowledge of an agent is to be imputed to a company principal has been considered in many cases but for present purposes I need only refer to Meridian Global Funds Management Asia Ltd v Securities Commission [1995] 2 AC 500 . In that case, Lord Hoffmann, in giving the advice of the Privy Council, said at page 507:

How then are these principles to be applied to s.70(2)(b) of the 1977 Act? Plainly this provision applies to companies and to individuals but, in the case of a company, whose knowledge is to be attributed to it? I did not understand Mr Watson to contend that the provision should apply only on the basis of a company's primary rules of attribution, so that, for example, what matters is the state of mind of its board of directors. On the other hand, it also seems to me unlikely that Parliament intended that the knowledge of any agent acting within the scope of his authority or any employee acting in the scope of his employment should be imputed to the company. That would be to impose a wholly unreasonable obligation upon a corporate patent department to make wide ranging enquiries throughout the whole company before it seeks to enforce a patent.

So I consider this is one of those cases where we must look to see whose knowledge was for the purpose of this provision intended to count as the knowledge of the company. Where, as here, a company has secured the grant of a patent and then seeks to enforce it, to limit that knowledge to that of an uninformed patent attorney in the patent department who writes a threatening letter would, in my judgment, be too restrictive. A patent attorney only learns about the invention because it is reported by the inventor. The patent attorney then has to ascertain from the inventor which features distinguish the invention from the prior art and he has to exercise great skill in drafting a detailed description of the invention in precise legal terms. It seems to me that it would be wholly wrong for a company to take advantage of a breakdown in communication between the patent attorney and the inventor which results in the company securing a patent of unjustified scope. So if a company has applied for and secured the grant of a patent and then seeks to enforce it, the controlling mind of the company must include at least the mind of the properly informed patent attorney or, put another way, the minds of the patent attorney and the inventor.

In this case the first threatening letter, dated 4 May 2015, was written by Mr Heiko Conze, the Director of Sales and Marketing of the first Defendant. Mr Conze prepared witness statements for use in these proceedings and although he referred in terms to the 4 May 2015 letter, he said nothing which might relate to any defence under s. 70(2A).

On 9 May 2016 Mr Bottema, the third Defendant and managing director of the first Defendant, sent a number of threatening letters on behalf of the second Defendant to the Claimant and a large number of its customers and potential customers. He did not give evidence before me. Indeed, no witness led any evidence to support a defence under s. 70(2A) and Mr Campbell invited me to infer that the reason for this was that such a defence did not exist on the facts.

Mr Platts-Mills, however, drew my attention to an opinion prepared by a Mr Jan Walaski of Venner Shipley LLP and dated 19 April 2016. Mr Walaski’s view was that the P is valid and is infringed by Icescape’s device. Mr Platts-Mills invites me to infer from this that in May 2015 and May 2016 the Defendants did not know and had no reason to suspect the P was invalid in any respect.

There are problems with Mr Platts-Mills ’ invitation. The first is that I was not provided with the instructions upon which Mr Walaski based his opinion. Moreover it appears that Mr Walaski did not consider priority at all, basing his opinion entirely on a prior art search he conducted in the context of novelty and inventiveness. In these circumstances, Mr Walaski’s opinion appears to have no value at all.

The second problem is that the person responsible for sending the letters did not condescend to reveal whether or not he knew or suspected that the patent was invalid in any material respect. In circumstances where a party chooses not to lead evidence about the state of mind of a particular individual where that state of mind might be highly relevant and there is no explanation offered, the court will be slow to infer a state of mind in his favour. Indeed, it is hard to conceive of a state of affairs where it would do so, there being no reason for it.

In these circumstances, I am satisfied that s. 70(2A) does not provide the Defendants with a defence to the threats claim. Thus the action succeeds in every respect.