AIPPI’s Amicus Brief Committee Activities regarding G 1/23 and G 1/24 of EPO Enlarged Board of Appeal

The Enlarged Board of Appeal (EBA) of the European Patent Office (EPO) has been busy this summer!

The EBA handed down two eagerly awaited decisions, in cases G 1/24 (18 June 2025), and G 1/23 (2 July 2025) within just a few weeks of each other.

AIPPI’s Amicus Brief Standing Committee (ABC) has also been busy over the past year, as we filed Amicus Briefs in both cases!

Here’s what happened:

G 1/23 “Solar Cell” Case:

The invention concerned a solar cell sealing material comprising a polymer defined by features A, B, C, D, and E.

Document D1 disclosed the commercial product ENGAGE8400 as a suitable material for encapsulating solar cells.

Other documents disclosed that ENGAGE8400 had features A, B, C and D. As a result, ENGAGE8400 appeared to be a good candidate for closest prior art.

Document D18 disclosed how to produce ENGAGE polymers in general, but not specifically how to produce ENGAGE8400.

The Patent Proprietor argued that ENGAGE8400 was not part of the prior art since it could not be reproduced by the person skilled in the art without undue burden.

AIPPI argued that a previously decided EBA case, case G 1/92, is relevant to the present case.

Point 1. of the headnote of G 1/92 states that:

“The chemical composition of a product is state of the art when the product as such is available to the public and can be analyzed and reproduced by the skilled person, irrespective of whether or not particular reasons can be identified for analysing the composition.”

A contrario, if the product cannot be analyzed or reproduced, its chemical composition is excluded from the state of the art.

AIPPI, in accordance with G 1/92, submitted that a product cannot be considered as being comprised within the state of the art if it is not analyzable and reproducible for the person skilled in the art without undue burden.

The EBA decided, contrary to the opinion handed down in G 1/92, that if a product is available on the market, it forms part of the prior art.  The EBA has limited its opinion to the question of availability of the product, and specifically indicates that it will not address the question of enablement.  AIPPI’s amicus brief was specifically cited by the EBA as not being in line with their opinion.

AIPPI regrets that the EBA decided to overturn the clear and long-established case law of G 1/92. The new G 1/23 decision may have far-reaching consequences for patent proprietors, as it significantly broadens what can be considered as falling within the state of the art.  It will be of interest to observe how this case will ultimately be applied in a practical manner, in particular with regard to novelty and sufficiency of disclosure requirements.

G 1/24 “Gathered Sheet/Heated Aerosol” Case:

The issues at hand were:

• should interpretation of claims be performed in the same manner for invalidity and infringement (using Article 69 of the European Patent Convention and its Protocol)?
• should the description and figures always be consulted to interpret the claims, or only when the claim is unclear when read in isolation?
• is it possible to disregard an explicit definition in the description for interpretation of a claim?

AIPPI submitted that interpretation of claims should take into consideration the content of the description and the figures, and the method of interpreting claims should be the same, whether considering patentability of a patent application or infringement/validity of a granted patent.

AIPPI further submitted that a definition or information in the description may only be disregarded in exceptional cases where it is clearly contrary to the claim language.

The EBA decided (headnote of G 1/24):

“The claims are the starting point and the basis for assessing the patentability of an invention under Articles 52 to 57 EPC.  The description and drawings shall always be consulted to interpret the claims when assessing the patentability of an invention under Articles 52 to 57 EPC, and not only if the person skilled in the art finds a claim to be unclear or ambiguous when read in isolation.”

In the present case, the EBA’s position is in close agreement with that of AIPPI.

***

AIPPI’s Amicus Brief Committee is vigilant about identifying cases in all AIPPI member countries which might be good candidates for filing amicus briefs.  Relevant Standing Committees are consulted as part of the ABC’s Protocol, and the Patents Committee provided valuable insight in preparing the two amicus briefs discussed above.

If members identify possible cases for amicus filings by AIPPI, we urge you to contact ABC leadership!