EBA Referral G 1/23 – Is a marketed product excluded from the prior art if its composition could not be analysed without undue burden?

Graham Murnane (GB)

The Enlarged Board of Appeal (EBA) in case G 1/23 has given third parties the opportunity to file comments (amicus curiae briefs) on the questions referred to it by Technical Board of Appeal 3.3.03 in its interlocutory decision of 27 June 2023 in case T 438/19.

The EBA has set a deadline of 30 November 2023 for the filing written statements by third parties.

The referral seeks clarification on the enablement test for prior use of a product. The questions relate to the circumstances under which the prior use of a product may be excluded from the prior art for lack of enablement.

What constitutes prior art?

What constitutes prior art is a core issue for patent attorneys. We have all had to explain that a printed disclosure can be prior art, even if it has only had a limited circulation to a small group of people not bound to confidentiality. We have had to warn clients against exhibiting or even trialling their invention in a public space, before filing a patent application. This referral therefore appears to be significant for all patent attorneys.

The significance is not limited to the chemical field. Although G 1/92, cited in the referral, refers to the chemical composition of a product in the headnote, the headnote goes on to state that: “the same principle applies mutatis mutandis to any other product” (emphasis added).

As the Board in T 438/19 explained: “… the question at stake is of considerable practical relevance, rather than merely theoretical, as it potentially arises whenever the assessment of prior art involves the possibility to analyse and reproduce the chemical composition of a commercially available product.” The Board therefore found that the referral to the EBA was admissible and met the requirements of Article 112(1)(a) EPC.

What is the Enlarged Board being asked?

The referral particularly asks whether the non-enabling prior use of a product excludes the composition of the product from the prior art or whether it also excludes the product per se. This is of significance, because if the product per se is excluded it cannot be used as a starting point for an inventive step analysis. The referral also seeks clarification over the definition of enablement with respect to the prior use of a product, and particularly whether “enablement” requires that the skilled person be able to fully analyse and reproduce the exact same product. 

The questions are as follows:

The “state of the art” is defined by Article 54(2) EPC as “everything made available to the public by means of a written or oral description, by use, or in any other way, before the date of filing of the European patent application”.

According to the established case law (as discussed in EPO Guidelines for Examination, G-IV, 2) in order to constitute prior art, a disclosure must also be enabled

Also according to the established case law from the EBA (see G 1/92), if the invention is a product, prior disclosures of the product are only considered to have resulted in the chemical composition having been “made available to the public” if “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”.

Why is this referral being made?

Given that G 1/92 has been with us so long, why has this referral been made now? The reasoning given by the Board in T 438/19 is that they noted a divergence in how Boards have interpreted a potentially confusing paragraph in G 1/92. Paragraph 1.4 of the Reasons for the Decision in G 1/92 reads as follows:

The Board in T 438/19 held that the last sentence of this paragraph (in bold above) could appear to indicate that a product put on the market becomes state of the art and therefore available to the public only when the composition or internal structure of the product can be discovered and reproduced without undue burden. This seems at odds with the conclusion of G 1/92 which states that “the product as such is available to the public”.

Diverging approaches in applying G 1/92

The Board identified diverging approaches adopted in the case law of the Boards of Appeal in applying G 1/92. In particular the Board identified divergent decisions with regard to the following aspects:

According to one body of case law, in cases where a product that was publicly available before the priority date of a patent could not be analysed or reproduced by a skilled person, only the internal composition of the product should be excluded from the prior art (T 370/02, T 2045/09, T 1833/14, T 0023/11). According to another body of case law, both the product per se and its internal composition should be excluded from the prior art (T 946/04, T 1666/16). 

The referring Board in T 438/19 argued that the distinction over whether the composition of the product, or both the product and its composition, should be excluded from the prior art is not just a theoretical question, but has practical consequences for inventive step analysis. If a product per se is excluded from the prior art, it cannot then be used as a starting point for inventive step in combination with other prior art documents, e.g. documents about the product that may assist in overcoming the enablement issues. Importantly, the enablement test permits the skilled person to use common general knowledge (CGK) but not prior art documents that do not form part of the CGK.

Comments on the referral

Many patent attorneys will have their own views on how G 1/92 should be applied, in order to provide certainty with regard to prior art disclosures.

Chris Mercer, the chair of the European Patent Practice Committee (EPPC), is coordinating the epi’s own amicus curiae brief, for consideration by the Enlarged Board in G 1/23. He would welcome any volunteers to help with the drafting of the brief. He would also welcome any comments from epi members as to what should go into the brief. He can be reached, with comments or offers of assistance, at the general EPPC email address (eppc@patentepi.org).

We await the decision in G 1/23 with interest.

Comments