EPO Enlarged Board of Appeal Referral G1/23 – Extent of Disclosure of Prior Use
The first referral of 2023, case G1/23, has been made to the Enlarged Board of Appeal (EBA) of the EPO, seeking clarification on the enablement test in relation to prior use of a product. In particular, the question raised is whether the non-enabling prior use of a product exclude only the composition of the product from the prior art, or is product itself is also excluded? While the referring case relates to chemical compositions, the findings could be more widely applied to devices which can be analysed to determine their internal structure and function such as mechanical devices, or systems made of multiple components.
The prior art is defined as being everything made available to the public by means or written or oral description, by use or in any other way before the date of the filing of the application. This includes prior use. However, for a disclosure to be prior art, it must also be enabling. Under established case law from the EBA (G1/92), prior disclosures of a product are only considered as being made available to the public if the skilled person would have been able to analyse and reproduce the product using common general knowledge.
The referral comes from T0438/19 which relates to polymers for coating and protecting cells within solar panels. The case hinged on whether prior use of the polymer ENGAGE 8400 was considered prior art. This polymer was commercially available prior to the filing date of the application, so the issue was whether this was an enabling disclosure of the product. It was argued that the skilled person could not reverse engineer the product, as it would be an undue burden to determine the specific catalysts and reaction conditions required to make the polymer.
For 30 years under established European case law, a commercially availability product has been considered prior art if it meets certain requirements:
1) the product must be available to the public;
2) the skilled person must be able discover the composition or internal structure of the product; and
3) the skilled person must be able to reproduce the product using common general knowledge without undue burden.
If all these criteria are met, then both the product and its composition or internal structure become prior art. In cases where the product cannot be analysed or reproduced, there have been diverging decisions on how the decision in G1/92 should be interpreted. In some cases only the internal composition of the product is excluded from the prior art, but in others both the product and its internal composition are excluded from the prior art.
The issue of whether only the composition, or both the product and its composition should be excluded from the prior art has practical consequences in situations where the issue of inventive step is being considered. If the product itself is excluded, then it cannot be used as a starting point for assessing inventive step in combination with other prior art documents.
The Board of Appeal has referred the following questions:
1. Is a product put on the market before the date of filing of a European patent application to be excluded from the state of the art within the meaning of Article 54(2) EPC for the sole reason that its composition or internal structure could not be analysed and reproduced without undue burden by the skilled person before that date?
2. If the answer to question 1 is no, is technical information about said product which was made available to the public before the filing date (e.g. by publication of technical brochure, non-patent or patent literature) state of the art within the meaning of Article 54(2) EPC, irrespective of whether the composition or internal structure of the product could be analysed and reproduced without undue burden by the skilled person before that date?
3. If the answer to question 1 is yes or the answer to question 2 is no, which criteria are to be applied in order to determine whether or not the composition or internal structure of the product could be analysed and reproduced without undue burden within the meaning of opinion G 1/92? In particular, is it required that the composition and internal structure of the product be fully analysable and identically reproducible?
The decision of the EBA is not likely to be issued before 2024. However, it would be a major shift in practice if a product was completely excluded from the prior art solely because some part of it was difficult for the skilled person to analyse or reproduce. Some clarity on the threshold or test for enablement to establish if a product is part of the prior art for assessing novelty and/or inventive step is expected, but we wait to see how the EBA deal with this tricky issue.
In the meantime, the EPO has now issued a Notice that the President has decided to stay all examination and opposition proceedings where the decision depends entirely on the outcome of this referral. The examining or opposition division will inform the applicants where a stay is applied. Any outstanding deadlines on a stayed case will be withdrawn.
