This progress is reshaping traditional notions of what constitutes a technical contribution in the field. As the tools for generating and characterising antibodies become more sophisticated and widely available, patent offices are re-evaluating how they assess key legal requirements such as inventiveness and sufficiency of disclosure.
A changing playing field for patentable antibody invention
In this evolving context, the standards for what qualifies as a patentable antibody invention are becoming increasingly demanding — both in Europe and in the United States.
The USA
In the United States, antibodies can still be claimed by their function — for example, by their ability to bind a particular antigen or block a biological interaction.
However, the Supreme Court’s decision in Amgen v. Sanofi has significantly raised the bar for such claims. The Court reaffirmed the long-standing principle that “the more one claims, the more one must enable” — a notion both intuitive and now firmly reinforced in US jurisprudence.
In practice, this means that functional claims must be backed by a robust set of representative examples and evidence demonstrating a predictable structure-function relationship. A general reference to “an antibody that binds protein X” will no longer suffice.
Applicants are expected to provide detailed sequence information — ideally for several antibodies — as well as comprehensive supporting data, such as binding affinities, epitope mapping, and functional assays. Genus claims remain theoretically possible, but they must be enabled across their full breadth to survive scrutiny.
The European Patent Office
At the European Patent Office, the approach has traditionally been more conservative, and recent developments reflect a continued tightening of the requirements, in particular with regard to sufficiency of disclosure and inventive step: the EPO generally expects antibodies to be structurally defined — preferably by all six CDRs or by the complete variable regions.
Broad functional definitions are accepted only in limited circumstances, and only where there is extensive experimental support and a clearly demonstrated technical effect. Where the target antigen is already known, merely identifying a new binding antibody is rarely enough to establish inventive step. Applicants must instead demonstrate an unexpected property — such as binding to a novel epitope, enhanced affinity, or a distinct functional effect.
Moreover, reliance on post-published data to establish technical contribution is generally not permitted, although such data may be used to support effects that are already made plausible in the application as filed.
Multi-jurisdictional protection
For applicants seeking protection in both jurisdictions, it is often advisable to prepare the description and experimental examples with EPO requirements in mind.
In both the US and Europe, combining structural and functional elements in claim language tends to offer the most practical and legally robust approach. The USPTO may still permit broader claim scope where the data is strong, but the EPO continues to favour more narrowly defined and precisely characterised inventions.
Concluding thoughts
When I was a young associate, I was once told that it borders on malpractice to file claims so narrow that the patent is granted without objection. More than 30 years later, I still believe in aiming broad — but only if the description and examples provide sufficient support for the likely amendments that may follow. In the life sciences, and in antibody-related inventions in particular, this is not a trivial exercise. It requires thoughtful claim drafting and close collaboration between inventors and patent attorneys from the very beginning.
FICPI's view and involvement
FICPI uniquely combines education and advocacy on topics around patents and trade marks, with a focus on developing the professional excellence of its individual members. FICPI Forums, Congress, committees and meetings are opportunities to gather insights from the international IP attorney community on any issue, whether it be practice-related or topics of patent and trade mark law.
Next steps
- Read the report AI and patenting pharmaceuticals from FICPI's Executive Committee meeting workshop (Goa, 2024).
- Explore the FICPI Study & Work Groups and get more involved with FICPI’s work, including its Working Group on Biotechnology and Pharmaceuticals (CET 5).