Irreproducible Products and the implications of G 1/23
21 February 2025
In the run-up to the oral proceedings for G 1/23 (“Solar cell”), due to be held on 12 March 2025, we consider the potential changes in practice at the European Patent Office (EPO) in relation to the disclosures of irreproducible products.
Previously, in G 1/92, a cumulative test was set in order to determine whether the chemical structure of a product is state of the art. A criterion of the test was the requirement that the product should be reproducible by the skilled person without undue burden (termed the “enablement requirement”).
This often resulted in irreproducible products being excluded from the state of the art.
An irreproducible product is a complex material which cannot be easily reverse engineered due to a lack of knowledge of suitable processes and/or starting materials. Irreproducible products arise in many areas of technology, for example complex polymers which have compositions and structures which are largely a function of their method of manufacture (e.g., specific temperatures, initiators, catalysts, solvents, etc). Such methods are often kept secret by manufacturers, meaning the products are irreproducible.
Irreproducible products fail to meet the enablement requirement and are not considered to be state of the art, meaning that such chemical structures cannot be used in the assessment of novelty or inventive step of patent applications for related products (or indeed a patent application for the same product with sufficient disclosure to then render it reproducible).
A divergence has, however, developed in the application of the G 1/92 test in what exactly is excluded from the state of the art when considering irreproducible products. One interpretation is that it is the chemical composition of the product which is excluded from the state of the art, while the product per se remains state of the art (T 946/06; T 1666/16). A counter interpretation is that the product in its entirety is excluded from the state of the art, including its chemical composition (T 1833/14; T 23/11; T 370/20; T 2045/09).
Additionally, there is ambiguity in whether technical properties disclosed along with an irreproducible product are to be included in the state of the art (e.g., the product data sheet of a complex polymer disclosing the density, hardness, viscosity, and the melt-flow rate).
Referred Questions
Considering this, the Enlarged Board of Appeal (EBoA) have been referred the following three questions to bring greater clarity and uniformity:
Q1: 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?
Q2: 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?
Q3: 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 G1/92? In particular, is it required that the composition and internal structure of the product be fully analysable and identically reproducible?
Preliminary Opinion
In August last year, the EBoA issued its preliminary, non-binding, opinion that the answers to questions 1 and 2 should be NO and YES, respectively, with question 3 then being rendered moot.
The EBoA reasoned that the answer to Q1 had to be NO because the skilled person could not ignore the existence of a product which is already on the market, often widely advertised and used. Additionally, the EBoA noted that the enablement requirement should not be applied to irreproducible products, which should instead be considered enabled by their state of existing. The EBoA opined that the answer to Q1 being NO meant that the answer to Q2 would have to be YES. Specifically, the EBoA noted that all analysable properties and features of the product should also be part of the state of the art.
In his reply to the preliminary opinion, the President of the EPO largely agreed with the preliminary opinion of the EBoA, noting that practice at the EPO would have to change if the enablement requirement of products were separated from other forms of disclosures (e.g., documents).
Interestingly, one point of disagreement between the President and the EBoA was the status of non-analysable features. The EBoA was of the opinion that it was undisputed that non-analysable features were not in the state of the art, while the President considered that excluding non-analysable features from the state of the art could potentially create a legal fiction where features that were present in a readily available product do not belong to the state of the art because they could not be analysed at the relevant date.
Implications
Currently, in Europe, an Applicant may be able to patent a product which has been available on the market before filing because the product is arguably irreproducible and thus not considered to be part of the state of the art. Should the final decision of the EBoA mirror that of the preliminary opinion then this would mark a significant change in practice at the EPO. It would mean that irreproducible products that were once excluded, would now be part of the state of the art. The European patent system would therefore adopt something akin to a US style on-sale bar, meaning that patenting irreproducible products in Europe after they have gone on the market would become significantly more difficult, if not impossible.
A number of questions remain outstanding, which should hopefully be clarified in the final decision of the EBoA, namely:
- Can the enablement requirement still be applied to other forms of disclosure, such as documents, given that disclosures tend to be treated by the same standards regardless of their form?
- Will this decision be limited to chemical/pharmaceutical products?
- Is it undisputed that non-analysable features are not disclosed by irreproducible products?
We look forward to reporting on the final G 1/23 decision in the coming months.
Bradley Wilson
Life Sciences & Chemistry group
This publication is a general summary of the law. It should not replace legal advice tailored to your specific circumstances.
© Withers & Rogers LLP February 2025
