Posted: October 25th, 2019
A Formstein objection in the UK? by Paul England, Taylor Wessing
As is now well-known, in Actavis v Eli Lilly ( UKSC 48) the UK Supreme Court held that direct infringement cannot be determined solely by whether a product or process falls within the language of the claim. Instead, whether variants falling outside the language of the claim may still infringe must be taken into account as a second step – in other words, a doctrine of equivalents applies. This is a development widely seen as an alignment with European patent law, particularly that of Germany.
Perhaps the paramount question that has arisen in the wake of the Actavis v Eli Lilly decision is: does the doctrine of equivalents apply to patent claims in the context of determining novelty or other validity objections? This matters in the UK, because the scope of claim of a patent has traditionally been construed consistently for the purpose of both infringement and validity. In other words, an infringing embodiment that post-dates the patent would necessarily anticipate the patent if it were of an earlier date – the ‘Merrell Dow principle’ ( RPC 76)). Doubt has now been cast on this simple relationship. Is it correct that a product which would not anticipate a patent if it was prior art, can now nonetheless infringe it if it post-dates that patent? Should, for validity purposes, some account be taken of equivalents?
The first suggestion that there may be a solution to this question came in a decision of the Intellectual Property and Enterprise Court (Technetix v Teleste  EWHC 126 (IPEC) (29 January 2019)). Here, HHJ Hacon entertained the idea that a Formstein type objection found in German law has a role in English cases, on the basis that it reflects the Merrell Dow principle. In Technetix, the judge held the patent invalid. Otherwise, the judge said it would have been infringed, unless there exists in English law a “Formstein defence”. If there is such a defence, the judge goes on, it would apply in this case.
Later, Mr Justice Nugee in the Patents Court (Emson v Hozelock  EWHC 991 (17 April 2019)), found that a patent for an expandable hose assembly would be infringed on the doctrine of equivalents. In his decision, Nugee J again discusses Formstein, although because the patent was held invalid his decision again did not turn on the issue.
What the British judges are referring to is the Formstein objection, which features in the approach to the doctrine of equivalents in Germany. as exemplified by Schneidmesser I (GRUR 2002, 515). If a variant is found to be equivalent using the three step approach to the doctrine of equivalents in Germany (exemplified by Schneidmesser I (GRUR 2002, 515), which itself resembles the three step approach used in Actavis), the Formstein objection (Formstein GRUR 1986, 803) is then employed as a fourth step. This asks: “Does the variant, having regard to the state of the art, lack novelty or is the variant obvious to a person skilled in the art?” HHJ Hacon in Technetix interprets this objection like this:
One way of reconciling the Merrell Dow principle with the doctrine of equivalents would be to say that if an accused product or process is an equivalent and for that reason is nominally within the scope of the claim, but the equivalent would have lacked novelty or inventive step over the prior art at the priority date, then it is deemed to fall outside the scope of the claim, thus providing a defence to infringement.
It remains to be seen whether the Formstein issue will re-surface on appeal of the Hozelock decision (Technetix is not being appealed), but it may prove to be the extra alignment with foreign law needed to answer a question raised by the earlier alignment in Actavis v Eli Lilly.
A longer version of this article was first published in MIP. The topic is also discussed in ‘A Practitioner’s Guide to European Patent Law‘, recently published by Hart Publishing.