6.2 Inventive step of antibodies 

The subject-matter of a claim defining a novel antibody binding to a known antigen does not involve an inventive step unless the application shows a surprising technical effect or there was no reasonable expectation of success in obtaining antibodies having the required properties (see G‑VII, 13). Examples of surprising technical effects include an unexpected improvement over prior-art antibodies in one or more properties, such as therapeutic activity, stability or immunogenicity, or an unexpected property not exhibited by prior-art antibodies.

Inventive step cannot be established solely on the basis that an antibody is structurally different from the prior-art antibodies. Arriving at alternative antibodies exclusively by applying techniques known in the art is considered to be obvious to the skilled person. The fact that an antibody's structure, i.e. its amino acid sequence, is not predictable is not a reason for considering the antibody to be non-obvious (see T 605/14, section 24; T 187/04, section 11).

Nevertheless, antibodies can be inventive if the application overcomes technical difficulties in generating or manufacturing them. A novel type of functional antibody format may also be considered inventive.