What forms part of the "state of the art" is critical to any assessment of novelty and inventive step. In its answer to the referral in G1/23 the Enlarged Board of Appeal has provided clarity on how reproductivity effects prior use disclosures for the purposes of an patentability assessment. The central issue was whether a product's inherent non-reproducibility should exclude not only the composition of the product, but also the product per se and any associated technical information, from forming part of the state of the art.
Legal background
In Europe, the novelty and inventive step of an invention are assessed in view of the "state of the art". Article 54(2) EPC states:
"The state of the art shall be held to comprise everything made available to the public by means of a written description, by oral description, by use, or in any other way, before the date of filing of the European patent application."
In other words, every public disclosure, in any form, is considered part of the state of the art. However, there remains an important nuance to the interpretation of this provision as to what it means for something to have been "made available" to the public. Particularly, if a product cannot be reverse engineered or reproduced without undue burden by a skilled person, how much can it be said that the product has been "made available"? In answer to this, in G 1/92, the EBA introduced an enablement requirement for prior art. According to G 1/92, the composition of a product only forms part of the state of the art when the product as such is available to the public and can be analysed and reproduced by the skilled person.
Case background
The EBA referral G1/23 stemmed from appeal proceedings in T 0438/19. In this case, the Opponent, Borealis GmbH, appealed against the Opposition Division's decision to maintain the Mitsui Chemicals patent EP 2626911
It was undisputed by the parties that the exact method for manufacturing the ENGAGE® 8400 polymer was not in the public domain when the patent was filed. It was also undisputed that reverse engineering and manufacturing ENGAGE® 8400 would not have been straightforward for the skilled person even if they had a sample of the product for analysis
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| Mysteries |
The Opponent by contrast argued that, whilst a skilled person would not have been able to exactly reproduce ENGAGE® 8400, they would have been able to make a sufficiently similar product if they knew about ENGAGE® 8400. For the Opponent, G 1/92 did not require the skilled person to be enabled to make an exact reproduction of the prior art product in order for the disclosure of the product per se (as opposed to its composition) to be enabling. Furthermore, the Opponent argued, just because ENGAGE® 8400 per se was not reproducible, it did not follow that all the information about ENGAGE® 8400 that a skilled person would be able to glean from its disclosure, did not thereby not form part of the state of the art.
Questions referred to the EBA
The Board of Appeal in the case found that if ENGAGE® 8400 and the technical information about ENGAGE® 8400 was part of the state of the art, it would prejudice inventive step even if the composition of ENGAGE® 8400 was not known. However, for the Board of Appeal, to answer this question, clarity was needed on how to interpret G 1/92. The Board of Appeal thus referred the following questions to the EBA:
Question 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?"
Question 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?"
Question 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 EBA's decision and reasoning
The EBA agreed with the referring Board of Appeal that clarity on the fundamental point of law concerning the legal boundaries of the state of the art
In its decision, the EBA went on to answer Question 1 with an unequivocal "No"
Similarly, Question 2 was answered "Yes"
As a result of the answers to Questions 1 and 2, Question 3 was deemed moot
The core of the EBA's reasoning in this referral rested on the rejection of an interpretation of G1/92 that creates a legal fiction whereby a non-reproducible product simply does not exist for the skilled person. For the EBA, this approach "would lead to absurd results when applied consistently"
The EBA further clarified that the term "reproduced" in G 1/92 should be understood in a broader sense, encompassing the ability of the skilled person to obtain and possess the physical product from the market
In G1/23, the EBA thus explicitly rejected the notion that the problem of reconstructing a product's properties is a technical problem for the skilled person that determines its prior art status per se. Instead, this is a "practical legal problem of proof for the lawyer" (r. 84)
Final thoughts
The decision in G1/23 thus rejects the notion that a product's non-reproducibility stops it from forming part of the state of the art. This decision therefore aligns the patent law with reality. For this Kat, it always required a certain degree of mental gymnastics to understand scenarios whereby all the information about a product made available to the public had to be excluded from the state of the art solely because the composition of the product was not known.
Speaking of mental gymnastics, the issues in this case reminds PatKat of the UK court's rather bizarre approach to prior use, whereby the mere "potentiality" of disclosure is considered state of the art. This approach can require similar mental gymnastics, and is an example of divergence between patent law and what most people would consider common sense...Anyone remember the infamous seed drill? (IPKat). Thankfully, in G1/23, as well as a recent Board of Appeal decision (IPKat), the EPO has signalled that it will take a practical and common-sensical approach to prior use. Let us hope the UPC follows suit.
Whilst the case at issue in G1/23 related to a complex polymer invention, the decision is of course highly relevant to any field of technology involving highly complex subject matter that it is difficult to reproduce, including pharmaceuticals and devices comprising "black-box" software. More on this to follow.
Further reading
- A more nuanced approach to the evidence standard for prior use (T 1311/21)
- New EBA referral: When is prior use of a product excluded from the prior art for lack of enablement?
- Mr Justice Nugee and the Superhose: The potentiality of disclosure
- Hacon HHJ and the Seed Drill: Intentionality in prior use (Claydon v Mzuri, [2021] EWHC 1007)
Reviewed by Dr Rose Hughes
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Posts
I commented this decision in my blog.
ReplyDeleteIt appears a priori acceptable and logical that a product put on the market can no longer be patented afterwards.
The problem is when the product is only known by a trademark, and nothing else is known about the product or how it can be obtained.
In view of existing case law, the problems posed by a product defined solely by a trademark, whether temporarily available or not, do not seem as easy to resolve as the EBA claims.
For example, in T 392/01 the product used was defined solely by a trademark "Cascotak ADP 21/494″, but this product has disappeared from the market and the patent has been revoked.
Claim 1 of AR4 in T 842/1, stipulates that the “antifoam reagent” be selected from a group of trademarked antifoam reagents, namely “1520-US, AF, FG-10, 0-30, SE-15, and Antifoam B”.
The parties agreed that they were all commercially available at the priority and filing dates of the patent, but their availability until the end of the patent term was disputed. The CR agreed and revoked the patent for insufficient disclosure.
A similar conclusion was reached in T 797/14.
According to G 1/23, these patents should never have been revoked. There is also a long line of case law to the effect that a non-enabling disclosure cannot be used against an application or a patent. See CLBA, 10th edition, I-C, 4.11. Has this case law become obsolete with G 1/23?
In T 522/14 and T 2020/14, the products used were only designated by trademarks, but the chemical composition was otherwise known. Hence no problem of sufficiency.
The comparison with prior public use for the availability of a product is an interesting point of view, but it does not follow from the existing case law that a product only known under a trademark must be available only at the filing date, but also throughout the life of the patent.
G 1/23 gives the appearance of a pragmatic decision, but on second reading, this character seems less manifest.
It will be interesting to see the impact of this decision on Rule 27(a) EPC, which provides that " [b]iotechnological inventions shall also be patentable if they concern: (a)biological material which is isolated from its natural environment or produced by means of a technical process even if it previously occurred in nature". G 1/23 not only refers to composition put on the market but also in several sections to compositions existing in nature (see para. 29, 58, 61, 62, 63,71). While these products-of-nature (incl. naturally occurring DNA and protein sequences) are not considered to be patentable subject matter in most legislation (due to their inherent lack of novelty), the Biopatent Directive 98/44 and in consequence the EPC has created a "novelty exception". G 1/23 may bring this back to the common practice. It will be interesting to see the impact especially on sequences encoding for "native traits", where trait is usually obtained from a publically available plant genetic resource.
ReplyDeleteG1/92 was a decision that dealt with the complicated issue of what was disclosed by a substance in the prior art that could be analysed. The present decision says in para 92:
ReplyDelete"All analysable properties of the product put on the
market became public alone by the possibility that they
could have been analysed, because the product was
physically accessible. If the composition could be
analysed, this became part of the state of the art as
well, also if the skilled person would not have been in
the position to reproduce it on their own."
This surely cannot be correct because many inventions arise due to the 'discovery' of previously unknown properties of substances, such as their ability to treat cancer. If all properties are deemed prior art then a lot of inventions are going to become obvious, and so para 91 of the decision cannot be correct. The Enlarged Board have done a good job here in terms of the enablement issue, but opened up a potentially problematic area in terms of which analysable properties are automatically prior art for a substance. Thank you Rose for the writeup
Santa, it is not (yet) clear whether the EBA's ruling in G 1/23 means that their reasoning in para 3 of G 1/92 is no longer valid.
ReplyDeleteI am inclined to believe that the reasoning in para 3 of G 1/92 remains valid:
" It may be added that a commercially available product per se does not implicitly disclose anything beyond its composition or internal structure. Extrinsic characteristics, which are only revealed when the product is exposed to interaction with specifically chosen outside conditions, e.g., reactants or the like, in order to provide a particular effect or result or to discover potential results or capabilities, therefore point beyond the product per se as they are dependent on deliberate choices being made. Typical examples are the application as a pharmaceutical product of a known substance or composition (cf. Article 54(5) EPC) and the use of a known compound for a particular purpose, based on a new technical effect (cf. G 2/88, OJ EPO 1990, 93). Thus, such characteristics cannot be considered as already having been made available to the public".
Thoughts?
As far as “ENGAGE 8400” is concerned, there is indeed a lot of information on the parameters it fulfils available, but there is no information about its actual composition, be it before the filing date of D1 nor presently.
ReplyDeleteIn D1, filed on 19.09.2007, “ENGAGE 8400” has been used to encapsulate a solar cell. In the more recently available information on “ENGAGE 8400”, the use of “ENGAGE 8400” is recommended for “Airbag Covers, Bumper Fascia and Panels, Consoles and Trim”, i.e. for the automotive industry. No word about the suitability for encapsulating solar cells.
I would therefore logically conclude that the use of “ENGAGE 8400” for encapsulating solar cells is not any longer advised by the proprietor of D1 and the manufacturer of “ENGAGE 8400”, as for both it is the Dow Company. How can such a product be part of the prior art?
In T 1293/13, claims 1 and 17 limit the determination of air permeability of the garment to a particular method “measured according to ASTM D737-96” and to a particular machine ”Frazier Low Pressure Air Permeability Machine 750”. The machine 'Frazier Low Pressure Air Permeability Machine 750' no longer exists, such that this machine cannot be used for determination of the claimed values. As the machine was not any longer available, the board held that the requirements of Art 83 were not fulfilled, and confirmed the revocation o the patent.
This situation is similar to that in T 392/01, T 842/14 and T 797/14 I quoted in my comments where the products were only known by their trademarks.
Thank you Proof of the Pudding. The new decision says 'All analysable properties...', but I agree that this probably excludes 'deliberate choices' being made as you have indicated. In G1/23 the EB wisely avoided going into this issue, and I know there is some case law on what such excluded deliberate choice properties as defined in G1/92 might be, such as binding to antibody X. My only real complaint against G1/23 is perhaps the lack of recognition in the decision of the lack of certainty that has been created by adding lots of substances to the prior art and not really defining which of their properties has become prior art. However I think the usual EPO inventive step analysis will adequately deal with this point on a case by case basis. Also it must be remembered that in reality this issue rarely comes up (in my experience) in examination or opposition, and so G1/23 does not need to be complete in every aspect of the test. Thank you again for responding. I didn't think anyone would be interested in this point.
ReplyDeleteSanta, you are welcome.
DeleteEven before you posted your comment, I had spotted that the most important question that was not fully resolved by G 1/23 was which properties of a product (intrinsic only, or literally any "analysable" properties) are deemed to enter the state of the art when a product is made available to the public.
I agree that the EBA was wise not to address certain questions, including when (or even whether) the issue of undue burden arises. However, it would have helped enormously if the EBA had explicitly indicated that the reasoning in para 3 of G 1/92 is still sound.
The rest of G 1/23 seems pretty straightforward to me. For example, I believe that it is absolutely clear that the EBA's ruling does not eliminate the requirement for a product to be "reproducible" in the sense of G 1/92. It is just that, in view of the EBA's reinterpretation of G 1/92, this requirement is now viewed as being "inherently fulfilled by a product put on the market" (G 1/23, Reasons 73).
I also believe that it is abundantly clear that G 1/23 does not in any way affect the interpretation of Article 83 EPC. Indeed, the EBA spells this out at G 1/23, Summary V:
"In the following, the formal legal term “state of the art” within the meaning of Article 54(2) and 56 EPC will also be referred to as “prior art”, the commonly used shorter term for the same concept. Also, the requirement of the reproducible prior art will also be referred to as the enablement requirement. Here this term is used solely in the context of the expected reproducible character of a disclosure for the purposes of Article 54(2) EPC, i.e. the prior art. Enablement within the meaning of Article 83 EPC is not treated in this decision".