Article 82 EPC: Unity of invention

Text of Article 82 EPC

In plain English

An application may claim several inventions only if they share a single general inventive concept. In practice the EPO looks for special technical features: features that make a contribution over the prior art and that are the same or correspond across the claims.

Lack of unity can be obvious from the claims as filed (a priori), or appear only after the search shows that the feature linking the claims is already known (a posteriori). The second case is common: claim 1 falls to the prior art, and the dependent claims turn out to go in unrelated directions.

Unity is mainly policed at the search stage. Under Rule 64 the search division searches the first invention and invites you to pay a further search fee for each additional one within two months. For Euro-PCT applications, Rule 164 does the same job. Whatever is not searched cannot be pursued in that application.

If you do not pay for an invention, G 2/92 says you cannot pursue it in this application; you have to file a divisional. If you pay and later convince the examining division the objection was wrong, the further search fees are refunded on request (Rule 64(2)).

Unity matters only up to grant. It is not a ground of opposition, and G 1/91 confirmed that a patent amended in opposition does not need to meet Article 82.

Key decisions

• G 2/92 : An applicant who does not pay further search fees for a non-unitary application cannot pursue the unsearched subject matter in that application and must file a divisional for it.
• G 1/91 : Unity of invention is not a requirement a European patent must meet when it is maintained in amended form in opposition.
• G 1/11 : An appeal against an examining division's refusal to refund further search fees under Rule 64(2), issued separately from grant or refusal, goes to a technical board.

Common objections

A posteriori lack of unity

Argue that the special technical feature is not anticipated, or identify another shared feature that is new and inventive. If the objection stands, choose which invention to keep and plan divisionals for the rest.

Different categories that do not correspond

A product, a process for making it and a use of it are unitary when they share the same inventive feature. A product and an unrelated process are not.

Drafting and prosecution tips

• Structure the claims around one inventive concept and make sure each independent claim includes it.
• Before paying further search fees, decide which inventions are worth a search now; the rest can go into divisionals with their own search.
• Keep claims to unsearched inventions out of later amendments: Rule 137(5) will block them.