Federal Circuit Rejects Request to Adopt New Inventorship Standards

Book about Patent Law and gavel.Earlier this month the Federal Circuit affirmed a district court’s determination that two scientists should be named as inventors in six U.S. patents obtained by Ono Pharmaceuticals.[1] 

35 U.S.C. § 116(a) provides the standard for joint inventorship:

When an invention is made by two or more persons jointly, they shall apply for patent jointly and each make the required oath, except as otherwise provided in this title. Inventors may apply for a patent jointly even though (1) they did not physically work together or at the same time, (2) each did not make the same type or amount of contribution, or (3) each did not make a contribution to the subject matter of every claim of the patent.

In order for one to be considered an inventor, one must contribute to conception (i.e., the mental aspect of inventing).[2]

Inventorship Dispute

The instant case stems from an inventorship dispute in patents related to groundbreaking cancer immunotherapy. The patents are directed to methods of treating cancer by administering PD-1 (programmed cell death 1) or PD-L1 (programmed cell death 1 ligand 1) blocking antibodies targeting specific PD-1/PD-L1 interactions on T cells.  Dr. Honjo, an inventor of these patents and a Nobel Prize winner for his discovery of PD-1, collaborated with Drs. Wood and Freeman, who discovered PD-L1, and discussed their development of anti-PD-L1 antibodies and the possible use of those antibodies in treating cancer.  Drs. Honjo, Wood, and Freeman published a joint research study announcing the discovery of the protein PD-L1 in 2000, prior to the filing of Dr. Honjo’s patent application in Japan in 2002.  Each patent at issue in this case claims priority from Dr. Honjo’s Japanese patent application; none include Drs. Wood and Freeman as inventors. 

Dana-Farber Cancer Institute, Dr. Freeman’s employer, brought suit alleging that Drs. Freeman and Wood should be added as inventors on Dr. Honjo’s patents based on their significant contributions to the conception of the invention in all six patents.  The district court agreed.

The Appeal

On appeal, Ono argued, among other things, that Drs. Freeman’s and Wood’s alleged inventive contributions should be deemed irrelevant to inventorship because their work with Dr. Honjo was published before conception of the patented inventions. In so arguing, Ono was asking the Federal Circuit to adopt a new rule – one that the Federal Circuit declined to adopt, stating instead that it was “an unnecessarily heightened inventorship standard.”[3] The court emphasized that a joint invention is simply the product of a collaboration between two or more persons working together to solve the problem addressed.[4]

Ono also asked the court “to hold categorically that research made public before the date of conception of a total invention cannot qualify as a significant contribution to conception of the total invention.”[5]  Again, the panel declined to adopt the rule proposed by Ono.  “Such a rule,” the court opined, “would ignore the realities of collaboration […].”[6]  Indeed, “[t]he inventorship of a complex invention may depend on partial contributions to conception over time, and there is no principled reason to discount genuine contributions made by collaborators because portions of that work were published prior to conception for the benefit of the public.  Earlier publication of an invention is obviously a potential hazard to patentability, but the publication of a portion of a complex invention does not necessarily defeat joint inventorship of that invention.”[7]


To be a joint inventor, i.e., a co-inventor, there is no requirement that the conception be of equal magnitude.  Nor is it necessary for each inventor to contribute to conception of all of the patent claims filed in order to be a joint inventor.  Rather, it is enough for one to contribute to conception of a single claim in order to be considered a joint inventor.  This is critical because, absent some agreement on ownership of invention rights, each joint inventor will jointly own any patent that issues.  Moreover, failure to name joint inventors may render a patent invalid.[8]  A person who contributed significantly to the conception of an invention should not be excluded from inventorship, and this case serves as a reminder of the importance of properly determining inventorship.

Related Blogs

“Well, I Do Declare!”

“Patents 4 Patients” Program Extended to 2022


[1] Dana-Farber Cancer Inst. v. Ono Pharm. Co., No. 2019-2050, (Fed. Cir. July 14, 2020).

[2] See, e.g., Burroughs Wellcome Co. v. Barr Labs., Inc., 40 F.3d 1223 (Fed. Cir. 1994) (“Conception is the touchstone of inventorship, the completion of the mental part of invention.”).

[3] Dana-Farber, slip op. at 10.

[4] Id.,  (quoting Fina Oil & Chem. Co. v. Ewen, 123 F.3d 1466, 1473 (Fed. Cir. 1997)).

[5] Id., slip op. at 12.

[6] Id.

[7] Id., slip op. at 13.

[8] See id., slip op. at 8 (“[A] valid patent requires correct inventorship.” (quoting In re VerHoef, 888 F.3d 1362, 1365 (Fed. Cir. 2018), as amended (May 7, 2018)).


We use cookies to give you the best online experience. By agreeing you accept the use of cookies in accordance with our cookie policy.