G 2/21: Enlarged Board of Appeal allows post-filed data to prove technical effect

So far, established European Patent Office case law requires that, in order for the examiners to account for data submitted after filing a patent, it must be plausible from the application as filed, in combination with common general knowledge, that the technical effect was already achieved at the date on which the patent was filed. Now the EPO’s Enlarged Board of Appeal (EBA) has confirmed this in its G 2/21 judgment.

G 2/21 clarifies questions

The EBA makes clear that, according to the principal of free evaluation, patent examiners must now consider such post-filed evidence. In the ruling, the judges state that:

1. Evidence submitted by a patent applicant or proprietor to prove a technical effect relied upon for acknowledgement of inventive step of the claimed subject matter may not be disregarded solely on the ground that such evidence, on which the effect rests, had not been public before the filing date of the patent-in-suit and was filed after that date.
2. A patent applicant or proprietor may rely upon a technical effect for inventive step if the skilled person, having the common general knowledge in mind, and based on the application as originally filed, would derive said effect as being encompassed by the technical teaching and embodied by the same originally disclosed invention.

Accordingly, the EPO may not reject an invention because data was not already available at the time of the patent application. In the future, the judgment will require examination divisions and the Opposition Division to closely scrutinise the data. Divisions will decide on a case-by-case basis when a technical effect is plausible and when it is not.

Dispute over insecticide composition

The G 2/21 case is based on a dispute between Sumitomo Chemical and Syngenta, concerning an opposition against Sumitomo’s EP 2 484 209. The patent protects insecticide compositions involving a combination of compounds for which the examples demonstrate synergy. Previously, Syngenta had claimed the patent lacked inventive step.

After the Opposition Division rejected the opposition in 2017, Syngenta filed an appeal in autumn 2020 (case ID: T 116/18). The Board of Appeal 3.3.02 stated that the question of inventive step depended on whether post-published data that supports the technical effect, upon which the patent owner relied, was admissible.

In its referral, the Board of Appeal also identified diverging strands of case law regarding the assessment of plausibility. Such is the significance of G 2/21 cases, JUVE Patent included it in its ‘Top 10 patent cases of the year 2022‘ round up in December of last year.

Plausibility not a legal concept

Furthermore, the EBA considered that the term “plausibility” did not amount to a distinctive legal concept or a specific patent law requirement under the European Patent Convention (EPC). Instead, the EBA considered that “it rather describes a generic catchword seized in the jurisprudence.” This correlates to the second point of the EBA’s ruling.

Parties have awaited the decision for several months. It could have implications for parties filing second medical use patents, where the question of plausibility often plays a big role. According to G 2/21, even stricter standards apply to these than to other patent applications.

Japan specialist

For years, Sumitomo has relied on the German patent law firm Winter Brandl for filing and prosecution, including for the patent-in-suit. As a patent attorney with European and Japanese qualifications, Kan Hasegawa especially represents Japanese clients in industry, as well as research institutes.

Syngenta is a long-standing client of UK patent law firm HGF, which has offices in the UK, Ireland, France, Switzerland, the Netherlands. Since the firm merged with Patronus IP in 2019, it also has capacities in Germany and Austria.

For Sumitomo
Winter Brandl (Freising): Kan Hasegawa (patent attorney)

For Syngenta
HGF (The Hague): Achim Krebs, Dominique Trösch

Enlarged Board of Appeal, European Patent Office, Munich
Carl Josefsson (chairman), Ingo Beckedorf, Fritz Blumer, Tamás Bokor, Paolo Catallozzi, Pascal Gryczka, Andrea Ritzka.