Article 69 EPC: Extent of protection

Text of Article 69 EPC

In plain English

Article 69(1) sets two rules. The claims, not the description, decide what is protected. But the description and drawings are used to understand what the claims mean. The Protocol on the Interpretation of Article 69, which is part of the Convention, says the claims are not to be read with strict literalness nor as mere guidelines.

Article 69(2) deals with the period before grant: the published claims define the provisional protection, but the patent as granted or amended later limits it retroactively, so far as protection is not extended.

Article 69 is addressed mainly to national courts and the Unified Patent Court in infringement cases. For years the EPO's Boards disagreed about whether and how much to use the description when judging patentability. G 1/24 (18 June 2025) settled it: the claims are the starting point and the basis for assessing patentability, and the description and drawings must always be consulted to interpret them, not only when a claim seems unclear.

Consulting the description is not the same as rewriting the claims with it. T 1473/19 explained that the primacy of the claims limits how far the description can change the meaning of a claim feature. A definition in the description can narrow or explain a term; an unclaimed feature in the examples does not become a claim limitation.

The practical effect is that the description now matters for novelty and inventive step at the EPO as well as in court. A glossary entry or a statement of what a term “means” can decide whether a citation anticipates. The skilled reader should approach the claims with a mind willing to understand and should rule out readings that make no technical sense (T 190/99).

Key decisions

• G 1/24 : The claims are the starting point for patentability, and the description and drawings shall always be consulted to interpret them, not only if a claim is unclear or ambiguous when read in isolation.
• T 1473/19 : Article 69 and its Protocol should be used to interpret claims at the EPO, including for Article 123(2), but the primacy of the claims limits how far the description can change a claim feature's meaning.
• T 190/99 : The skilled person rules out illogical or technically senseless readings and construes the patent with a mind willing to understand, taking the whole disclosure into account.
• G 2/88 (Friction reducing additive) : A change of claim category after grant is judged under Article 123(3) by the protection of the claims as a whole interpreted under Article 69 and its Protocol, not by national infringement law.

Common objections

Description gives a term a broader or narrower meaning

Since G 1/24, an examiner or opponent may read a claim term in the light of a definition in the description. If that reading is unhelpful, the usual cure is to amend the claim or, where allowed, adapt the description (see Article 84 and G 1/25).

Unclaimed limitation read in

Applicants sometimes argue that a claim is narrower because of what the examples show. Following T 1473/19, that argument rarely works against clear claim wording.

Drafting and prosecution tips

• Define the terms that matter in the description, deliberately and consistently. Those definitions will now be used at the EPO as well as in court.
• Avoid definitions that narrow a claim term more than you intend, and avoid using the same word for different things.
• Put real limitations in the claims. Do not rely on the description to narrow a claim that would otherwise lack novelty.