top of page
  • narendra97

Court Maintains Low Standard for Joint Inventorship

The Federal Circuit affirmed that two scientists should be added as inventors on six patents owned by Ono Pharmaceuticals for their contributions made public before the date of conception of the total invention. This holding maintains a lower standard for joint inventorship. Dana-Farber Cancer Institute, Inc. v. Ono Pharma Co. (Fed. Cir. 2020);

Six lucrative patents related to cancer therapies blocking PD-1 receptor/ligand interactions were at issue.

Beginning in 1998, Dr. Honjo collaborated with two U.S. scientists, Drs. Freeman and Wood, to find a ligand for the PD-1 receptor. The scientist generated substantial data and shared information and reagents. Drs. Freeman and Wood filed a provisional application in 1999 in the U.S.A. without listing Dr. Honjo. Dr. Honjo generated more results, and in 2002, filed his own patent application in Japan, which resulted in the patents at issue.

Dana-Farber, an employer of Dr. Freeman, eventually sued for correction of inventorship for the patents at issue arguing that Drs. Freeman’s and Wood’s research qualified them as inventors.

Ono argued that the subject matter of contributions of Drs. Freeman and Wood were not sufficiently close to the claimed invention and urged the court to adopt a legal rule that once a contribution is made public, it “no longer qualifies as a significant contribution to conception” because Drs. Freeman’s and Wood’s work with Dr. Honjo was published prior to the date of conception.

The court agreed with Dana-Farber. The court cited that “[t]o be a joint inventor, one must: (1) contribute in some significant manner to the conception or reduction to practice of the invention, (2) make a contribution to the claimed invention that is not insignificant in quality, when that contribution is measured against the dimension of the full invention, and (3) do more than merely explain to the real inventors well-known concepts and/or the current state of the art.” Pannu v. Iolab Corp., 155 F.3d 1344 (Fed. Cir. 1998).

The court noted that “joint inventors need not contribute to all aspects of a conception.” Eli Lilly, 376 F.3d at 1359–59; 35 U.S.C. § 116(a).

The court further noted that “conception is complete when an idea is definite and permanent enough that one of skill in the art could understand the invention. An inventor need not know, however, that an invention will work for its intended purpose in order for conception to be complete, as verification that an invention actually works is part of its reduction to practice.” Burroughs Wellcome, 40 F.3d at 1228.

The court concluded that “[e]arlier publication of an invention is obviously a potential hazard to patentability, but publication of a portion of a complex invention does not necessarily defeat joint inventorship of that invention.” Practice pointers related to this case include that when inventorship is in doubt, it is useful to perform an inventorship determination to memorialize (1) who contributed to the conception and reduction to practice of the invention and (2) the details of the role of each inventor. Additionally, when determining inventorship, it may be prudent to take a broad view of inventorship rather than a narrow one based on this holding.


Recent Posts

See All


A recent post from the USPTO that you may find helpful: USPTO broadens types of electronic signatures allowed for patent correspondence To provide better customer service, reduce barriers to practice


Leber IP Law is excited to be attending the NAMWOLF Driving Diversity & Leadership Conference (DDLC) in New Orleans in March. Shelly Fujikawa will be co-presenting a CLE on Shrinking Patent Rights an


Commenting has been turned off.
bottom of page