The First Casualty of G 1/24: T 0439/22 and the Article 123(3) Trap
In the first application of G 1/24, the referring Board revokes a patent after a description definition destroys novelty. The decision also highlights a severe Article 123(3) EPC trap when deleting definitions post-grant.

Picture the scene during opposition oral proceedings: the opponent cites a prior art document showing a spirally wound tobacco sheet, but your independent claim explicitly requires a "gathered sheet". You confidently argue that "gathered" means folded to occupy a three-dimensional space, not merely wound. The opposition division agrees, declining to consult a broader definition buried in the description because the claim wording seems perfectly clear on its face.
This was exactly the proprietor's successful strategy at first instance in T 0439/22. The patent, EP 3 076 804, concerned a heated aerosol-generating article. The opposition division maintained the patent, applying the traditional "primacy of the claims" approach to find the subject-matter novel over document D1. However, this case happened to be the very vehicle that prompted the referral to the Enlarged Board of Appeal resulting in G 1/24. When the case returned to Technical Board of Appeal 3.2.01, the landscape of European claim interpretation had fundamentally changed.
The holistic mandate in action
The Enlarged Board in G 1/24 ordered that the description and drawings shall always be consulted to interpret the claims, not merely when the skilled person finds a claim unclear or ambiguous. Applying this holistic approach, the Board turned to the patent specification.
Paragraph [0035] of the description explicitly defined "gathered" as denoting a sheet that is "convoluted, folded, or otherwise compressed or constricted substantially transversely to the cylindrical axis of the rod". The proprietor argued that the skilled person would still rely on their initial understanding of the claim wording and disregard this isolated passage. The Board disagreed. A skilled person reading the specification with a mind willing to understand will attribute considerable weight to any definition of a term used in the claims (reasons 3.4).
Because the definition was technically reasonable and did not contradict the overall teaching, the Board took it at face value. Under this broader definition, the spirally wound tobacco sheet in D1 was indeed "compressed or constricted substantially transversely" to the rod's axis. Consequently, the wound sheet equated to a "gathered sheet" (reasons 3.6). The main request lacked novelty.
The deletion dilemma
Faced with this novelty loss, the proprietor filed an auxiliary request with a seemingly straightforward amendment: they deleted paragraph [0035] from the description. The claims themselves remained entirely unchanged.
The opponent responded with an objection under Article 123(3) EPC, arguing that removing the definition broadened the scope of protection. The Board admitted this late-filed objection, noting it arose directly from the amendment.
The Board's analysis here is particularly instructive. Under the G 1/24 framework, the granted claim must be read in light of all aspects of a definition found in the description, taking into account both its broadening and limiting aspects (reasons 6). While paragraph [0035] broadened "gathered" to include "convoluted", it also limited the gathering to being "substantially transversely to the cylindrical axis of the rod".
By deleting this paragraph, the proprietor removed that implicit geometric limitation. Without the definition, the claim now encompassed aerosol-forming articles that were not rod-shaped, or sheets gathered along the cylindrical axis rather than transversely (reasons 6). The deletion of the description paragraph thus extended the scope of protection compared to the granted patent. The auxiliary request was refused, and the patent was revoked.
Practical implications
This decision illustrates the immediate, substantive bite of the G 1/24 framework. A definition in the description is no longer a mere fallback for ambiguous claims; it is an active, binding constraint on the scope of protection from the moment of grant.
For practitioners defending patents in opposition, the reflex to simply delete an inconvenient paragraph from the description is now fraught with risk. If a description passage acts as a lexicon that limits the interpretation of a granted claim, removing that passage will almost certainly trigger an Article 123(3) EPC trap. Moving forward, any attempt to escape a novelty objection by excising a broad definition must be carefully weighed against the danger of inadvertently expanding the claim's boundaries.
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Further Reading
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