Formstein defence in the UK? Technetix B.V. v Teleste Limited

Ever since Actavis v Eli Lilly ([2017] UKSC 48) dragged equivalence into the UK patent infringement system there has been an open question regarding the future of the so-called 'Gillette defence'. In particular, can a patent be valid over a piece of prior art (or an obvious modification thereof) which would fall within the scope of the claims under the Actavis questions. HHJ Hacon has waded into this in (1) TECHNETIX B.V, (2) TECHNETIX LIMITED and (3) TECHNETIX GROUP LIMITED v TELESTE LIMITED [2019] EWHC 126 (IPEC). There is also an exploration of the relevance of prior art and common general knowledge (CGK) when construing patent claims.

The Technology

The Patent, UK Patent No. 2 382 473 B, relates to a cable tap unit for receiving a cable tv or internet signal. The signal travels from its source of origin to a local distribution point, typically a street cabinet in the UK, and then on to a user's television or set-top box. As the signal strength will degrade during transmission, the signal received at the street cabinet is typically higher than can be received by the end user. The signal strength must be reduced before it can be read by the user's device and for this a directional coupler is used to "tap off" some proportion of the signal. This tapped-off signal is then fed into a splitter which splits the signal into a number of parts for multiple users.  The unit comprising these directional couplers and splitters is collectively referred to as a "tap unit". A UK street cabinet will contain many such tap units. 

Claim 1 of the Patent as granted was directed to a cable tap unit where the directional coupler is "detachable ... such that the signal transmission characteristics of the path are selectable by choice of directional coupler means".

A clarifying amendment was submitted specifying that "the directional coupler means is seperable from and insertable into the base unit independent of the group of signal outputs".

In essence, the Patent is directed to the idea of having easily replaceable couplers so that the amount of signal being tapped off can be altered as necessary. Typically, the entire tap unit had to be replaced to effect this change.

Kat enjoying the output from a cable tap unit

Common General Knowledge and Novelty

Following on from Regen Lab v Estar [2019] EWHC (Pat) (Summarised by GuestKat Rose Hughes earlier this week here), HHJ Hacon again raised the question of whether the CGK given as expert witness testimony was meant as CGK in the UK. This was addressed by assuming that this is what the witness meant.

The arguments regarding novelty centred upon the extent to which the judgement of Floyd LJ in Adaptive Spectrum and Signal Alignment Inc v British Telecommunications plc [2014] EWCA Civ 1462 should apply to earlier patent applications. In particular the Patentee cited from this case that "[107] Mr Wyand submitted that the court should be slow to arrive at a construction which resulted in a finding of invalidity for obviousness over common general knowledge". That is, if a prior art document forms part of the CGK should the claim be constructed to be novel over this document?

HHJ Hacon appears to not put much weight on this viewpoint, in particular when the alleged CGK included patent applications which were not cited in the Patent as filed. To this Kat this approach seems different to the approach taken in some of the UK Infringement and Validity Exam Papers (FD4/P6) for patent attorneys!

Novelty of claim 1 was attacked based upon United States Patent No. 5,058,198 to Rocci. The Patentee submitted that Rocci was not enabling as it did not allow removal of any directional couplers without physically affecting any signal outputs. HHJ Hacon was not convinced as he considered that this was not the actual requirement of claim  1 and indeed was "an impossibility".

The Patentee then submitted that tap units like Rocci were a part of the CGK and hence claim 1 should be construed to be novel over such an arrangement. HHJ Hacon "[found] this hard to follow" as the relevant part of the CGK would not deprive claim 1 of novelty. As such the construction of claim 1 should not be affected.

Claim 1 was therefore considered to lack novelty over Rocci.

In the event that Rocci was considered non-enabling for claim 1, HHJ Hacon considered claim 1 to lack inventive step over Rocci. In particular, the expert witness confirmed that the claimed invention would represent an obvious modification, but submitted that there were better starting points than Rocci. This was not convincing for HHJ Hacon.

The patentee attempted similar arguments for the second prior art document, United States Patent No. 6,292,371 to Toner which resulted in the same outcome. HHJ Hacon considered claim 1 to lack novelty and inventive step over Toner.

Infringement

Having already decided that the Patent was invalid as discussed above, HHJ Hacon moved on to consider whether Teleste's product would have infringed claim 1 if it were valid.

Teleste's defence argued that "if its product fell within the scope of claim 1, it was entitled to a defence to infringement if the product lacked novelty or inventive step over the prior art". This was summarised by HHJ Hacon as a "basic principle of patent law in the United Kingdom" and cited Merrell Dow Pharmaceutical Inc v H. N. Norton & Co Ltd [1996] RPC 76 and Gillette Safety Razer Co v Anglo-American Trading Co (1913) 30 RPC 465 as precedent for this.

However, according to HHJ Hacon "in modern practice this is not strictly a standalone defence to infringement". In particular, it was not clear how this defence applied when considering equivalents following Actavis. That is, could a non-inventive modification to a prior art document be considered to infringe a later Patent under the Actavis questions. It was HHJ Hacon's belief that it would be "surprising" if the Supreme Court intended to abandon the principle without specifically mentioning it.

German law, which has had infringement equivalents for longer than the UK, has already established such a defence - known as a Formstein defence from Case X ZR 28/25 Formstein GRUR 1986, 803. HHJ Hacon considered that the Supreme Court may look to introduce a form of Formstein defence into English law in order to preserve the established principles. The consideration of infringement was then undertaken under the hypothesis that such a defence exists.

HHJ Hacon concluded that the Teleste product does not fall under the normal construction of claim 1, but would fall within the scope of claim 1 pursuant to the "doctrine of equivalents". Based upon the evidence of the expert witness, it was decided that the product would also not be inventive over the common general knowledge.

On this basis, HHJ Hacon decided that if a Formstein defence exists in English law, Teleste would have been entitled to this defence.

Conclusions

It will be interesting to see the first case testing the Formstein defence on a Patent which has not already been found invalid. This Kat imagines that the UK Supreme Court or Court of Appeal could well end up having to decide such a case in the coming years.