Safestand Limited v Weston Homes PLC & Ors

On 19 December 2023 I handed down judgment in these proceedings. I found that three patents owned by the claimant (‘Safestand’) are valid and that the defendants (collectively ‘Weston’) have infringed the patents by the marketing of builders’ trestles.

Weston have now modified the design of their products in two ways and say that the new trestles (‘the Modified Trestles’) do not infringe.

Weston’s trestles in both original and modified form use brackets to secure kickboards. Kickboards are boards of low height, like a plank on its side, placed at the edge of a platform to prevent a person from accidentally stepping over the edge. They are held in place by brackets. In the judgment I found that the brackets used by Weston infringe one of the patents in suit. Of the two modifications made by Weston, one is directed to the design of their brackets (‘the Modified Brackets’). The other goes to the design of the trestles more broadly.

In March 2024 Weston filed a Re-Amended Defence and Counterclaim seeking a declaration of non-infringement (‘DNI’) in respect of their Modified Trestles and Modified Brackets. The DNIs are sought in relation to two of the three patents in suit at the trial, the other having expired.

One of the surviving patents, European Patent No. 1 660 738 B1 (‘EP 738’) claims a builders’ trestle having certain features. The other, UK Patent No. 2 420 822 (‘UK 822’), claims a kickboard bracket with stated features. I will refer to them collectively as ‘the Patents’.

Safestand filed a Re-Re-Amended Reply and Defence to Counterclaim stating that the Modified Trestles and Modified Brackets still infringe. It is not asserted that they infringe on a normal construction of the Patents, only under the doctrine of equivalents.

Weston served a Reply in which they say:

Safestand’s case on infringement in relation to the modified designs will now go to trial, subject to applications made by each side.

On 29 May 2024 Safestand filed an Application Notice seeking an order striking out Weston’s Formstein defences. Safestand say that Weston’s arguments on novelty and inventive step in relation to Kelk amount to a rerun of an issue decided in my judgment of 19 December 2023 and should be struck out on the ground of issue estoppel or abuse of process. As to Weston’s arguments based on the Safestand Prior Disclosure, Safestand say that this amounts to an attempt to resurrect a dismissed reliance on this allegation and is an abuse of process.

On 6 June 2024 Weston filed an Application Notice seeking an order striking out Safestand’s allegations of infringement by equivalence in their entirety and for judgment to be entered in favour of Weston’s case for declarations of non-infringement. Weston contends that Safestand is now presenting its case based on inventive concepts of the Patents which are different from the inventive concepts relied on at the trial. They say that Safestand’s case on equivalents should be struck out (a) on the ground of estoppel, (b) because it contravenes the principle that a party is not entitled to approbate and reprobate or (c) because it is an abuse of process.

At the hearing of both applications Henry Edwards appeared for Safestand, Nick Zweck for Weston.

This is an illustration of Weston’s original trestles from the judgment:

The invention claimed in EP 738 is a safety feature which concerns the horizontal rails on the working side. In the photograph they are above the wooden platform and on the side of the trestles adjacent to what looks like a metal door. These (grey) horizontal rails and the (blue) uprights to which they are attached are removeable.

Weston’s original infringing trestles have removeable horizontal rails and uprights. The Modified Trestles have removeable horizontal rails but the uprights are fixed.

The kickboard brackets of UK 822 are shown in Figure 1:

The feature marked 70 at the back of the bracket hooks over a kickboard on the long side of the platform. A plank is slotted into the space or socket marked 64 to form a transverse kickboard. Weston’s infringing brackets have the features just mentioned and also the lateral extensions on each side at the back of the bracket, marked 76 in the figure.

Weston’s Modified Brackets do not have the lateral extensions, otherwise they are the same as before.

In Safestand’s pleaded case on equivalence relating to EP 738 this is the stated inventive concept:

Summarising Safestand’s case, it argues that the presence of fixed uprights in the Modified Trestles does not affect the key advantage provided by the inventive concept. Applying the Actavis questions (Actavis UK Ltd v Eli Lilly & Co [2017] UKSC 48, at [66]) leads to the result that the Modified Trestle infringes EP 738 as an equivalent.

This is Safestand’s pleaded case on the inventive concept of UK 822:

Safestand argues that removing the lateral extensions makes no difference in that the Modified Bracket still provides all the advantage of the inventive concept. As with the Modified Trestle, its pleading sets this out in more detail, running through the Actavis questions which are said to lead to infringement by equivalence.

The Formstein defence was explained in Technetix BV v Teleste Ltd [2019] EWHC 126 (IPEC) at [85]-[100]. In brief, a product or process which would nominally fall within the scope of a claim as an equivalent pursuant to the law on equivalents as explained in Actavis UK Ltd v Eli Lilly & Co [2017] UKSC 48 will be deemed to fall outside the claim’s scope if the equivalent would have lacked novelty or embodied no inventive step over the prior art at the priority date of the patent in suit.

The two items of prior art relied on by Weston in their Formstein defence, Kelk and the Safestand Prior Disclosure, both featured in the judgment of 19 December 2023.

In the pleadings in the substantive action Weston alleged that EP 738 is invalid and one pleaded ground was that EP 738 lacks an inventive step over Kelk. The obviousness of EP 738 over Kelk is discussed in the judgment.

The Safestand Prior Disclosure became part of the case on the first day of the trial when Weston applied to amend their pleading on novelty and inventive step to introduce reliance on the Safestand Prior Disclosure. I dismissed the application, giving reasons in the judgment.

I should add that in the DNI case Weston has pleaded arguments alternative to the ones I have mentioned: the scope of a patent claim is for all purposes expanded to include all equivalents; if in its expanded form the claim is not new or lacks inventive step over the prior art, an assertion of infringement by an equivalent must fail. Nothing was made of these alternative arguments at the hearing.

Weston pointed out that at the trial Safestand’s formulation of the inventive concept of EP 738 included the feature of removeable uprights, the very feature which the Modified Trestles do not have. That feature has now been dropped from Safestand’s inventive concept.

Likewise, Weston said, the lateral extensions of the invention in UK 822 featured in Safestand’s inventive concept for that patent at the trial. Now that this feature has been discarded in the Weston’s Modified Brackets, it is also missing from Safestand’s new inventive concept.

At the hearing Weston advanced its argument in support of striking out Safestand’s pleadings on equivalents by reference to the law on approbate/reprobate, accepting that if they did not succeed under this head, they would not succeed by reference to the law of estoppel or abuse of process.

Express Newspapers plc v News (UK) Ltd [1990] 1 WLR 1320 concerned a dispute between two newspapers, the Daily Express and Today. The plaintiff brought a claim against the defendant which had substantially copied a report in the claimant’s newspaper without acknowledging the source of the story. The plaintiff obtained summary judgment for infringement of copyright. There was a counterclaim in which the defendant complained that the plaintiff had copied a story in the defendant’s newspaper, described by the court as the mirror image of the plaintiff’s claim. The defendant sought summary judgment on its counterclaim.

The plaintiff ran a defence to the counterclaim based on a custom in the press of adopting stories which have appeared in rival newspapers. Sir Nicholas Browne-Wilkinson V-C held that the plaintiff had an arguable defence based on this alleged custom. Nonetheless he granted summary judgment because the plaintiff’s ground for resisting summary judgment was wholly inconsistent with its case in the main claim, a claim based on legally indistinguishable facts. He identified the point of law at 1329:

Express Newspapers was considered by Veronique Buehrlen QC in MPB v LGK [2020] EWHC 90 (TCC). Having quoted from the Vice-Chancellor’s judgment, she said:

In my judgment Weston’s application should be dismissed for reasons which can be shortly stated. I accept that Safestand has modified its case on the inventive concepts of the two patents. However, Safestand’s case at the trial did not constitute an election between options in the sense indicated by Sir Nicholas Browne-Wilkinson or Ms Buehrlen, or rather not an election by which it is now bound. That is because Safestand must now argue its case on infringement based on my findings in the judgment, subject only to contrary findings on appeal. I do not decide here whether Safestand is correct to say that its new formulations of the inventive concepts are consistent with the contents of my judgment, but it is certainly arguable and the point must go to trial.

I can see that if a party were to advance one formulation of an inventive concept in a claim and an inconsistent one in a counterclaim in the same proceedings, the doctrine of approbate/reprobate may have application. That is not this case.

Weston’s application is dismissed.

The law on issue estoppel is well established and was not in dispute. In Arnold v National Westminster Bank plc [1991] 2 AC 93 Lord Keith said, at 105:

In Virgin Atlantic Airways Ltd v Zodiac Seats UK Ltd [2013] UKSC 46, Lord Sumption, with whom the remainder of the court agreed, said (at [22]) that the House of Lords’ judgment in Arnold was authority for the following proposition, among others:

In my judgment I found that EP 738 does not lack inventive step over Kelk, making the following finding:

Thus, an issue I decided was that a trestle with a selectively removeable safety barrier on the working side would not have been contemplated by a skilled person reading Kelk. It was a necessary part of my holding that EP 738 was not obvious over Kelk and therefore a necessary ingredient in the conclusion that Weston’s cause of action for revocation of EP 738 did not succeed.

The Modified Trestle still has a selectively removeable safety barrier on the working side. At the present hearing I asked Weston’s counsel how it could advance its Formstein defence to infringement of EP 738 by reference to Kelk without inviting the court to reconsider that same issue. He accepted that the issue would have to be reopened but said that the law on the Formstein defence was new in this country, in a process of development, and as a matter of policy it should not be restricted.

I cannot accept this. The Formstein defence is indeed at a formative stage in this jurisdiction but I have no doubt that however it develops it will not override the law on issue estoppel as explained at the highest judicial level. Weston’s counsel rightly did not suggest that the Formstein defence falls within the exception stated by Lord Sumption, namely special circumstances that would cause injustice. Aside from anything else, I can see no injustice.

Weston’s Formstein defence made by reference to Kelk falls to be struck out.

I introduced the alleged prior use this way in my judgment:

I discussed the law on late applications of this nature, specifically the judgment of Carr J, as she then was, in Quah Su-Ling v Goldman Sachs International [2015] EWHC 759 (Comm) and that of the Court of Appeal in Nesbit Law Group LLP v Acasta European Insurance Company Limited [2018] EWCA Civ 268.

The judgment in Quah included this:

In Nesbit Law the Chancellor said:

In the judgment I applied the balance identified in the two cases just mentioned to Weston’s application to amend their Grounds of Invalidity and made this finding:

Weston argued that Safestand’s application to strike out this aspect of Weston’s Formstein defence stood or fell by the rule in Henderson v Henderson 3 Hare 100.

Referring to Test Claimants in the FII Group Litigation v Revenue and Customs Commissioners [2021] UKSC 31, at [74]-[77], Weston submitted that the issues were (i) whether Weston could and should have raised Formstein defences at trial and (ii) whether it is abusive to raise them in this DNI claim. Self-evidently, Weston continued, the defences could not have been raised at the trial because the trial was not concerned with the Modified Trestle or Modified Bracket.

Weston further argued that the time to raise the objection now being raised by Safestand was when Weston raised its DNI claim after the trial. Having consented to the claim, Safestand could not object to how Weston made the claim.

Safestand argued that Weston’s resurrection of its prior use allegation would be an abuse of process, whether under the rule in Henderson v Henderson or more generally. I was referred to the judgment of Potter LJ in Divine-Bortey v Brent London Borough Council [1998] ICR 886, at 898:

A parallel was drawn by Safestand with cases in which a party seeks to amend its claims after the court has ruled on the claims at trial. In Generics (UK) Limited v Warner-Lambert Company LLC [2016] EWCA Civ 1006, Floyd LJ, with whom Patten and Kitchin LJJ agreed, applied the law on abuse of process, including Henderson v Henderson, to an application to amend patent claims after the trial. He considered the distinction drawn by Jacob LJ in Nikken Kosakusho Works v Pioneer Trading Company [2005] EWCA Civ 906, at [8], between applications to amend claims (a) before the trial, (b) after the trial where the application is simply to delete claims found to have been invalid and (c) post-trial applications in which the patentee seeks to rewrite claims. Floyd LJ said:

Safestand submitted that the need for finality in litigation, expressly referred to in Nesbit Law, is exactly the need which underpins the rule in Henderson v Henderson and that this is clear from the judgments in Divine-Bortey and Generics v Warner-Lambert.

In the judgment in this case it was found that the Safestand Prior Disclosure could and should have been pleaded in good time before the trial, the judgment noting the consequence if Weston were now allowed to rely on the allegation: a further trial. That finding was not appealed. Safestand submitted that the same reasoning applies to Weston’s application to run a Formstein defence based on the Safestand Prior Disclosure – again the consequence would be a further trial. Prior use allegations are notoriously factually intensive and time consuming. This court has rejected Weston’s application to run the point in a second trial once; a further attempt to run the point in another trial is as unmeritorious as it was before and should be refused.

I do not agree with Weston’s analysis of the relevant issue now before the court. Certainly, Weston could not have pleaded the current Formstein defence before the trial because the Modified Trestle and Modified Bracket were not in play. The issue, however, is whether Weston is entitled to frame its case in relation to the DNIs now being sought in a manner which once again raises the question of the alleged Safestand Prior Disclosure.

Both sides argued that the resolution of that issue depends on the criteria applied in the rule in Henderson v Henderson.

On the present facts there is going to be a second trial anyway. This was not pressed by Weston at the hearing and I think for good reason. Absent the issue of prior use, it is likely that the trial of the application for DNIs, based on the findings in the judgment, will be short, requiring no evidence and only brief argument. A trial which included the resolution of the whether there was a Safestand Prior Disclosure would be substantial in terms of evidence and argument. It can always be argued that raising an issue late merely transfers the cost in time and money from an earlier trial to a later one, but courts have never been receptive to such an argument because in practice such a transfer generates extra cost in time and money and increased use of court time.

In my view it would not be in conformity with the rule in Henderson v Henderson if Weston were to be permitted to argue its case on the Safestand Prior Disclosure when, as I have already found, Weston could and should have pleaded that case in good time for it to be argued at the substantive trial. The vice entailed in having the opportunity to argue the case has not gone away. It would still be an abuse.

Weston once again raised a policy issue, saying that in this context too there should be no restriction imposed on the development of the law on Formstein defences. In my view this policy point lacks merit as it does in the context of the Formstein defence advanced by reference to Kelk.

Safestand’s application succeeds on both limbs. Weston’s Formstein defences will be struck out.