Decision of the referring board: T 0438/19 27-06-2023
Central to the assessment of novelty and inventive step at the EPO is the definition of ‘state of the art’ i.e., what disclosures can be considered as prior art when assessing whether an invention is new and nonobvious. Article 54(2) EPC defines the state of the art as ‘everything made available to the public’ before the effective filing date, be that the filing date or the priority date, of a patent application. But when the thing made available to the public is a product with a defined chemical composition, how much of that composition is made available to the public by the simple disclosure of the product? G 1/92 taught that the chemical composition of a product made available to the public is state of the art if the product can be analysed and reproduced by the skilled person. But what if the skilled person can analyse the product to some degree but can’t reproduce it in its exact form? Thus, how enabling does a disclosure need to be to be considered part of the state of the art? This is the very point at issue in the new referral to the EPO’s Enlarged Board of Appeal (EBA).
Background to the referral
The referral comes from Board 3.3.03 in the consideration of T 0438/19, an appeal against the decision of the opposition division to reject an opposition against European patent no. 2626911 directed to a material for encapsulating a solar cell which comprises an ethylene/alpha-olefin copolymer with certain defined properties, including a content of aluminium element of from 10 to 500ppm.
Although the opposition was filed on the grounds of lack of sufficiency as well as lack of inventive step, and in T 0438/19 the Board considers both aspects, it is the inventive step challenge that is the focus of the present referral.
In more detail, Example 3 of prior art document D1 disclosed a commercially available copolymer, ENGAGE® 8400, suitable for the manufacture of solar cell modules having all of the features of claim 1 of EP2626911 except the aluminium content. The opponent/appellant thus used Example 3 of D1 as the closest prior art for their inventive step challenge.
The Patentees’ rebuttal, to the extent relevant for the present discussion, was that ENGAGE® 8400 cannot be reproduced (i.e., it is not enabled) and therefore it has not been made available to the public within the meaning of Article 54(2) EPC and thus is not a suitable starting point for the assessment of inventive step. Referring to G 1/92, the Patentees argued that the availability to the public within the meaning of Article 54(2) EPC of ENGAGE® 8400 would require that the skilled person is able to produce a polymer that it is not somewhat similar to, but is exactly ENGAGE® 8400 and this without undue burden.
The appellant contested the Patentees’ reproducibility argument, alleging that irrespective of the extent to which the ENGAGE® 8400 polymer could be reproduced, certain properties of the material, which are covered by the claimed subject-matter, were in the public domain and it would be incorrect and unreasonable if such publicly available information of a commercially available product could be disregarded on the basis that the specific commercial material could not be exactly reproduced.
Against the above-described background, Board 3.3.03 in T 0438/19 grappled with how to interpret G 1/92.
As alluded to above, G 1/92 concerns the interpretation of “made available to the public” in Article 54(2) EPC in the context of prior use of a product.
G 1/92 concludes as follows:
The chemical composition of a product is state of the art when the product as such is available to the public and can be analysed and reproduced by the skilled person, irrespective of whether or not particular reasons can be identified for analysing the composition.
Providing further insight into the above conclusion, at paragraph 1.4 of the reasons, the EBA in G 1/92 stated that:
An essential purpose of any technical teaching is to enable the person skilled in the art to manufacture or use a given product by applying such teaching. Where such teaching results from a product put on the market, the person skilled in the art will have to rely on his general technical knowledge to gather all information enabling him to prepare the said product. Where it is possible for the skilled person to discover the composition or the internal structure of the product and to reproduce it without undue burden, then both the product and its composition or internal structure become state of the art.
Thus, of central importance is understanding to what degree a commercial product must be reproducible to be considered as comprised in the state of the art.
Reasoning for the referral
When trying to answer this question, the Board identified diverging decisions on three aspects relevant to the interpretation of G 1/92:
(i) interpretation of “available to the public” leading to the exclusion from the state of the art within the meaning of Article 54(2) EPC of the product itself (including its chemical composition/internal structure) or only of its chemical composition/internal structure,
(ii) the degree of detail required for the analysis of said product and
(iii) the requirements for its reproducibility.
With respect to (i), the Board found that different Boards of Appeal have reached diverging conclusions when it was found that the product put on the market could not be analysed or reproduced, deciding either that (a) its chemical composition (or internal structure) was not state of the art or that (b) the product itself was not state of the art, thus including its chemical composition or internal structure.
With respect to (ii), the Board found that whilst some Boards took as a criterion the exact composition of the product, in other decisions such a strict condition was not required.
With respect to (iii), the Board found that whilst some Boards have taken as a criterion the ability to exactly reproduce the product, in other decisions such a strict condition has not been required.
Questions referred to the Enlarged Board of Appeal in G 1/23
With the above in mind, Board 3.3.03 in T 0438/19 referred three questions to the Enlarged Board of Appeal:
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?
Whilst it might be another year before a final decision is issued, the composition of the Enlarged Board that will hear the case has been announced and all of (i) the parties to the appeal from which the present referral is derived (ii) the President of the EPO and (iii) third parties have been invited to file their observations by 30 November 2023. So far, only one amicus curiae brief has been filed.
Significant updates will be duly reported as they occur.