The decision of the Enlarged Board of Appeal (EBA) in G 2/21 on the use of post-published evidence to support patentability, was self-confessedly vague and open to interpretation (IPKat). Since G 2/21, Boards of Appeal have united on the interpretation that the evidence standard for inventive step (the "plausibility/credibility test") remains unchanged. With regards to the disclosure requirement for the technical effect relied on for inventive step, the Boards of Appeal have further adopted a patentee friendly interpretation of G 2/21, whereby the application as filed does not need to provide evidence of, or even to explicitly mention, the technical effect (T 0116/18, T 1989/19, T 2465/19). The recent decision in T 1994/22 delineates the boundaries of this broad interpretation, and provides guidance on the absolute minimum disclosure requirements for a technical effect.
G 2/21 case refresh: Reliance on post-published evidence
In G 2/21, the EBA considered the question of whether post-published evidence could be taken into account for inventive step. The EBA ordered that:
"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" (Headnote II, G 2/21)
G 2/21 was interpreted by the referring Board of Appeal as meaning that, in order to be relied on for inventive step, the application as filed does not need to either include a positive statement or experimental evidence of the technical effect (see e.g. T 2465/19, IPKat). According to the Board of Appeal in T 0116/18 (the referring Board in G 2/21), a technical effect must merely be "conceptually comprised" in the broadest technical teaching of the application as filed ("encompassed") (IPKat). Additionally, according to T 0116/18, the evidence standard with respect to a technical effect relied on for inventive step remains whether a skilled person would have substantiated doubts with respect to the invention or its purported technical effect, in view of the application as filed and common general knowledge. The Board of Appeal in T 0116/18 equated this test with that of whether the technical effect is "embodied" by the technical teaching of the application as filed.
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Pharmaceutical forms |
The Opponent in the case at issue in T 0116/18 filed a petition of review of the decision (R4/24), arguing that the Board of Appeal employed a new legal test in its written decision on which the Opponent was not given an opportunity to comment. However, the preliminary opinion of the EBA is that the petition for review is clearly unallowable (IPKat).
Case Background: Polymorph patents
In the recent decision T 1994/22, the patent (EP3275871) related to a particular crystalline form (polymorph) of the vasodilator drug selexipag. Selexipag is marketed as Uptravi for long-term treatment of pulmonary arterial hypertension (PAH). Different polymorphs of the same drug may have different chemical and physical properties that may, for example, enhance the stability or bioavailability of the drug. The patent protecting the commercialised polymorph of a drug may therefore provide valuable exclusivity. In this case, the selexipag polymorph patent was opposed on the grounds of lack of inventive step. T 1994/22 related to the appeal of the Opposition Division decision to uphold the patent as granted.
In T 1994/22, the Opponent argued that the claimed selexipag polymorph lacked inventive step in view of the patentee's expired composition of matter patent for selexipag (EP1400518 A1). In response the patentee submitted post-published data purporting to show that the claimed polymorph had improved photostability compared to an alternative polymorph. The application as filed provided no evidence for the photostability of the claimed polymorph. The application as filed in fact made no mention of the photostability of the claimed polymorph, or even polymorphs in general. The Board of Appeal considered whether inventive step could be supported by the post-published data in view of G 2/21.
The Patentee cited the interpretation of G 2/21 provided in T 0116/18 that the particular technical effect relied on for inventive step need not be explicitly disclosed in the application as filed. The Patentee argued that the application as filed included statements that the disclosed invention related to a novel polymorph an a high quality and stable pharmaceutical product. As such, the Patentee argued, the skilled person would have understood that the effect of improved photostability was implied by, or at least related to, the technical problem initially suggested in the originally filed application. The Patentee further submitted that the skilled person would have had no reason to doubt, in view of common general knowledge and the application as filed, that the purported improved photostability could be achieved with the claimed polymorph (the plausibility/credibility test, IPKat).
A specific technical effect is not encompassed by a sweeping statement of a high quality product
In its decision, the Board of Appeal in the case agreed with the interpretation of G 2/21 provided in T 0116/18 that "the purported technical effect together with the claimed subject-matter need only be conceptually comprised by the broadest technical teaching of the application as filed". However, the Board of Appeal did not agree that even this low bar was met in the case in question. Particularly, the Board of Appeal did not agree that the broad sweeping statements provided in the application as filed that "a quality product" was provided, could be considered to encompass improved photostability. In the words of the Board of Appeal: "If such a sweeping statement was sufficient, a reference to high quality would be sufficient to invoke whatever technical effect as being encompassed by an application as filed in the sense of G 2/21. This would essentially render the first criterion of order no. 2 of G 2/21 meaningless".
The Board of Appeal concluded that, whilst it agreed with the interpretation of G 2/21 provided in T 0116/18 (and T 1989/19, see IPKat), the case in question was different. Applying G 2/21, the Board of Appeal found that photostability was not encompassed and thus not derivable from the teaching of the application as filed in the sense of G 2/21.
The encompassed and derivable technical effect must be related to the claimed subject matter
The Board of Appeal further found that, even if it was found that improved photostability would be inferred by a skilled person from the application as filed, the skilled person would still not have recognised that this property was associated with the specifically claimed polymorph. The application as filed referred to three polymorphic forms in equal terms. Therefore, in contrast to T 1989/19, the Board of Appeal found that the case was not one in which the purported improvement would be understood from the application as filed as a property of the claimed subject-matter. The Board of Appeal thus concluded that the post-published data on the photostability of the claimed polymorph could not be relied on for inventive step.
The Board of Appeal went on to find that the application as filed demonstrated no unexpected properties of the claimed polymorph. The claims were therefore found to lack inventive step in view of the composition of matter patent, and the patent was revoked.
Final thoughts
The interpretation of G 2/21 on which the Boards of Appeal have coalesced is relatively patentee friendly (IPKat). The decisions in T 0116/18, T 1989/19, T 2465/19 found that, provided that a technical effect relied on for inventive step is somewhat broadly related to the disclosure provided in the application as filed ("encompassed and embodied"), it may be relied on for inventive step with the use of post-published data. Similar to T 0258/21, which found that G 2/21 does not permit armchair invention (IPKat), T 1994/22 provides a common-sense limitation to this broad interpretation: broad sweeping statements that a high quality product is provided do not in themselves encompass and embody a specific, undisclosed, technical effect.
Further reading
- Plausibility demystified - a review of EPO case law before G 2/21 (Feb 2023)
- G 2/21: Is the technical effect embodied by the invention as originally disclosed? (March 2023)
- To encompass and embody: Applying the abstract principles of G 2/21 (May 2023)
- The relevance of G 2/21 to machine learning inventions (T 2803/18) (Aug 2023)
- Interpretation of G 2/21: Inventive step may be supported solely by post-published data (T 0116/18) (Sep 2023)
- Reliance on a silent technical effect: Application of G 2/21 to semiconductors (T 2465/19) (Oct 2023)
- G 2/21 does not permit armchair inventing (T 0258/21) (Oct 2023)
- Clarity on the interpretation of G2/21 from the referring Board (T 0116/18) (Nov 2023)
- Crystallising the interpretation of G 2/21 (T 1989/19) (Dec 2023)
- Petition for review filed in referring decision to G2/21 (T 0116/18) (Jan 2024)
- Stretching the cheese: Contradictory evidence for a purported technical effect relied on for inventive step (T 0629/22) (May 2024)
![Crystal clear? G 2/21 applied to polymorph patents (T 1994/22)](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi08CXG8_lijQUTKnCI7BSAqPSYpts0pm5PP6xivxr7MaHO4DkWkJRTgLRryOHc1C-gRtj2HYRqRMpqCks4oKO18I_yzPKrgZ-F0e8alA-jRMkvshtP_Dpjq7-OuUa2WJDT2q0_agNCfT40u-k2Wuib0Aqv72y3ZBeQ3qnw_azxMJplvKsfuGDN/s72-c/rosepatkat_happy_silver_tabby_British_shorthair_surrounded_by_p_c0eb2e2c-e3c4-4607-8918-f0ebfd778d2b.png)
It is clear that the application of G 2/21 has been rather favourable to applicants or proprietors. I am inclined to claim that the boards are not always credible in their application of G 2/21.
ReplyDeleteTo be honest, T 116/18 is difficult to follow. The buzzword “synergy” has, in my opinion be misused by the proprietor and the board. There was a synergy originally disclosed, but for different pests. To use an American statement, I am not convinced that the proprietor was at the filing date in possession of the invention as it was eventually claimed.
In T 1989/19, the stability originally disclosed was the stability during manufacture. In appeal the proprietor came up with stability during storage. As the patent related to a medicament, there cannot be any surprise that the medicament should be stable during storage. The buzzword “stability” was enough to save the patent. This goes a bit far.
In T 2716/19, the proprietor came up two weeks in advance of the OP before the OD with experimental data about storage stability he kept before him a report for 18 years! The OD had not admitted the experimental data, but the board revised the decision of the OD not to admit it for the sake of G 2/21.
In T 2716/19, the question which arises is the following: is it reasonable to admit and use under G 2/21 a document which was in possession of the proprietor for 18 years before he brings it in the procedure? Reasonable doubts are permitted, even if the applicability of G 2/21 can as such not be contested.
According to T 2465/19, it was not necessary for the technical effect to be recited in the application as filed. This is a rather generous application of G 2/21 which is difficult to follow. That the examination reveals a different CPA than that know by the inventor is rather common. Construing an artificial effect on the basis of this CPA looks rather odd.
In T 887/21, the board made clear that a mere hypothesis in the application as filed, without any experimental data supporting said hypothesis, is not enough to admit post- published evidence in the meaning of G 2/21. If post-published evidence is not supported by the original disclosure, it cannot help defining the OTP.
In T 681/21, the board held that in the absence in the original description of the mention of a synergy effect, it is much more difficult to justify IS on a later alleged synergy effect. At least, the post-published submitted experimental data has to convincingly prove the alleged synergy across the entire scope of the claim.
In T 1994/22, the application as filed made no mention of the photostability of the claimed polymorph, or even polymorphs in general. A sweeping statement that "a quality product" was provided, could not be considered to encompass improved photostability. T 1994/22 is following the line of T 681/21.
Not only T 1994/22, but T 681/21 and T 887/21, delineate the boundaries of a possible interpretation of G 2/21, and provide guidance on the absolute minimum disclosure requirements for a technical effect.
T 1989/19, T 1989/19, T 887/21, T 681/21 and T 2716/19 were all commented in another blog.