Rule 80 EPC: when amendments in opposition are allowed
Rule 80 EPC governs when a European patent may be amended in opposition proceedings. Under Rule 80 EPC, the description, claims and drawings may be amended, but only where the amendment is occasioned by a ground for opposition under Article 100 EPC, even if that ground was not raised by the opponent. This guide sets out what the rule requires and tracks how the Boards of Appeal have applied it.
What Rule 80 EPC says
Rule 80 EPC is the gateway for amending a patent in opposition. Without prejudice to Rule 138 EPC, the description, claims and drawings may be amended, provided the amendments are occasioned by a ground for opposition under Article 100 EPC, even where the opponent has not invoked that ground (Rule 80 EPC). The test is one of purpose: an amendment must be a genuine response to an opposition ground, not an unrelated improvement or a tactical restructuring of the claims. An amendment that clears the Rule 80 gateway must still satisfy the other requirements of the Convention, in particular Article 123(2) and (3) EPC.
The "occasioned by a ground for opposition" test
Whether an amendment is occasioned by a ground for opposition is assessed on the substance, not the label. Deleting or limiting a claim to meet a novelty or inventive-step objection is occasioned by a ground; adding fresh independent claims, or splitting one claim into several to broaden the proprietor’s position, generally is not, unless the change genuinely answers an opposition ground. The proprietor carries the burden of showing that connection (Rule 80 EPC).
How the Boards of Appeal apply Rule 80 EPC
The admissibility of an amendment under Rule 80 EPC is a question of law the Boards review in full. They ask whether each amendment responds to a ground for opposition and refuse those that do not, even where the amendment would otherwise comply with Article 123 EPC. The decisions below show how that assessment has developed, and where individual Boards have drawn the line differently on claim splitting, new claim categories, and clarificatory changes. Each summary is the Board’s own catchword or headnote (Rule 80 EPC).
Rule 80 EPC in the case law
Rule 80 EPC has been cited in over 378 published Board of Appeal decisions. The most substantive recent ones, most recent first:
- T 0561/23Board 3.5.01
Zur Frage der Ersetzung eines unabhängigen Anspruchs durch mehrere unabhängige Ansprüche durch Einbeziehung abhängiger Ansprüche unter Regel 80 EPÜ, siehe Punkte 21 bis 26 der Entscheidungsgründe.
- T 0558/21Board 3.5.06
1. Sur la pertinence de l'appartenance d'une invention à un « domaine technique » pour son caractère technique et pour l'identification des caractéristiques qui y contribuent, cf. points 29 et 42. 2. Sur la contribution technique d'une méthode mathématique de génération d'un point sur une courbe elliptique utilisé dans une application cryptographique, cf. point 40. 3. Sur la détermination des caractéristiques d'une invention qui contribuent à son caractère technique dans le cadre de l'approche COMVIK, cf. point 41.
- T 2328/22Board 3.2.01
Umfang des Beitritts (Gründe 1.5.7) Anpassung der Beschreibung (insbesondere Gründe 6.5.5)
- T 2108/22Board 3.4.02
Inwiefern die Ersetzung eines Anspruchs durch einen Anspruch mit mehreren Alternativen unter Regel 80 EPÜ zulässig ist, muss im Einzelfall geprüft werden. Dabei ist nach Abwägung der gegenläufigen Interessen der Beteiligten zu prüfen, ob die Vervielfachung an sich von Alternativen in dem Anspruch eine sachdienliche und erforderliche Änderung darstellt (Entscheidungsgründe 1.10).
- T 1789/22Board 3.3.04
1. For considerations about the object of appeal proceedings and the rights of a non-appealing party, see Reasons, points 1 to 4. The provisions of Article 107, second sentence, EPC guarantee a non-appealing party the right to participate to pending appeal proceedings. However, they do not provide it an autonomous right to have requests which go beyond the scope of the appeal as defined by the appellant's statement of grounds of appeal, decided by the board (as a direct consequence of G 2/91, Headnote). By not filing an appeal, a non-appealing party has not contested the findings of the opposition division, beyond the framework of the appeal filed by the appellant. 2. A proprietor cannot be expected to file an amended description in appeal proceedings until an allowable set of claims is found. The lack of an adapted description constitutes no obstacle to the admittance of an amended set of claims into the appeal proceedings (see Reasons points 6.3 and 6.4).
- T 0123/22Board 3.2.02
Für die Beurteilung, ob eine Änderung von Ansprüchen im Sinne der Regel 80 EPÜ durch einen Einspruchsgrund veranlasst wurde, ist es unerheblich, ob die in einen angegriffenen Anspruch zusätzlich aufgenommenen Merkmale aus abhängigen Ansprüchen oder aus der Beschreibung stammen; siehe Nr. 3.6 - 3.7 der Gründe. Zur Beurteilung, ob das Erfordernis der Regel 80 EPÜ bei Ersetzen eines von einem Einspruchsgrund betroffenen unabhängigen Anspruchs durch mehrere unabhängige Ansprüche erfüllt ist, siehe Nr. 3.8 - 3.12 der Gründe.
- T 0431/22Board 3.2.05
Zur Ersetzung eines erteilten unabhängigen Anspruchs durch mehrere unabhängige Ansprüche siehe Punkt 1 der Entscheidungsgründe.
- T 0447/22Board 3.2.05
1. On the limits of claim interpretation in the light of the description (see point 13 of the reasons). 2. In application of decision G 3/14, an objection under Article 84 EPC that a claim is not supported by the description is open to examination in opposition or opposition appeal proceedings only when, and then only to the extent that, the lack of support has been introduced by an amendment to the patent. It must thus be accepted that the removal of an inconsistency between the description and a claim amended in opposition or opposition appeal proceedings is not possible when the inconsistency previously existed in the patent as granted (see point 83 of the reasons).
The chat knows every EPC rule and article, the Guidelines for Examination, the Official Journal, and the decisions of the Boards of Appeal and the Enlarged Board. Put a Rule 80 question from your own opposition to it.
Chat about Rule 80Frequently asked questions
Rule 80 EPC allows the description, claims and drawings of a European patent to be amended in opposition proceedings, but only where the amendment is occasioned by a ground for opposition under Article 100 EPC, even if the opponent did not raise that ground.
Only if the new claims are occasioned by a ground for opposition. Adding claims, or splitting an existing claim to strengthen the proprietor’s position without answering an opposition ground, is generally not admissible under Rule 80 EPC.
They are separate hurdles. Rule 80 EPC asks whether an amendment is occasioned by a ground for opposition; Article 123(2) and (3) EPC ask whether it adds subject-matter or extends the protection conferred. An amendment must clear both.