G1/23 Enlarged Board of Appeal confirms that publicly available products count as prior art

On 2 July 2025, the Enlarged Board of Appeal (EBA) in G 1/23 decisively resolved a key question referred in T 0438/19, namely whether a commercially available product that cannot be analysed or reproduced by the skilled person nonetheless forms part of the prior art under Article 54(2) EPC. The EBA decided that the mere fact that a marketed product cannot be analysed or reproduced does not exclude it from the state of the art.

To refresh your memory, the Board in T 0438/19  (EP2626911) had referred the following questions to the EBA for clarification regarding an alleged public prior use.

• 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?
• 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?
• 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 first question has been answered in the recent decision with a “No” and the second question with a “Yes” meaning that the third question does not need answering. But how will these answers impact European patent practice?

A broad interpretation of prior art

The EBA has effectively broadened the term “reproduce” to include simply acquiring the physical product from the market, not necessarily manufacturing it anew. This means that anyone being able to purchase a product is sufficient for that product to comprise part of the prior art. It is no longer necessary for a skilled person to be able to reverse engineer a product, determine its composition or internal structure, then make it themselves.

In addition, any publicly available technical information about the product (e.g. datasheets and brochures) is also to be considered as prior art, irrespective of whether the product the information relates to could be broken down and reproduced.

Reinforcement of the need to file a patent application before launch

This decision makes it clear that patent applications must be filed before commercialisation of a product. Once a product has been made publicly available, e.g. through sales, open demonstrations or distribution without confidentiality restrictions, the product now unequivocally qualifies as prior art under Article 54(2) EPC. It is no longer relevant whether the product was technically inaccessible due to a complex composition or structure.

This particularly impacts certain sectors including:

• Pharmaceuticals (e.g. crystalline forms or polymorphs),
• Advanced materials (e.g. composites or alloys), and
• Semiconductors and coatings, where structural details are hard to detect.

We recommend close coordination between R&D teams and patent professionals (whether in-house or within an external law firm). Ensuring filing timelines are aligned with market readiness should ensure that the filing of a patent application does not delay market launch and the launch of a product does not prevent a granted patent from being obtainable.

Opposition tools expanded

Third-party oppositions can now rely on any previously marketed product since a marketed product now qualifies as prior art even without having evidence of its composition or how it was manufactured. A new arsenal of prior art may now be used in oppositions, particularly where technical documents are limited but evidence of commercial activity is more readily available.

This means opponents can use:

• archived product brochures,
• datasheets or catalogues,
• packaging materials,
• user guides,
• evidence of product purchase (e.g. invoices, shipment records),
• trade fair presence, including samples or display evidence, and
• prior use.

Even if a single one of the above listed forms of evidence does not disclose the full invention, they may still be used to piece together evidence of a novelty-destroying disclosure.

Interpretation of novelty and inventive step

Novelty

In accordance with the clarified interpretation of “the state of the art”, a commercially available product forms part of the prior art regardless of whether its internal features were analysable at the time. However, to anticipate a patent claim, the claimed feature must have been objectively present in the product and be directly and unambiguously derivable from it, even if this derivation happens after the fact (e.g. via later analysis or expert evidence). This removes the buffer previously created by non-analysability. A product “as it is” now has the potential to anticipate even if its internal composition or workings are obscure to the skilled person.

Inventive step

The EBA distinguished between what forms part of the state of the art (availability) and what the skilled person would derive from it (content). The technical contribution of a product might still require inventive activity to uncover, especially if it is hidden or obscured.

Distinguishing novelty from inventive step

This decision states that a non-reproducible product belonging to the state of the art should not necessarily be treated equally when assessing novelty and inventive step.

• For novelty the test is strict: was the product publicly available?
• For inventive step the test is nuanced: what would the skilled person reasonably understand or derive from the available product?

Conclusion

G 1/23 brings clarity to a complex area of European patent law. By decoupling “availability to the public” from “enabling disclosure,” the EBA has confirmed a principle that aligns with practical and commercial reality: what is sold without restriction is disclosed, whether or not its secrets are discernible. This decision reinforces the importance of prior art searching beyond literature and databases and into the marketplace itself.