Dana-Farber v. Ono: Joint Inventorship and the PD-1 Immunotherapy Patents

Dana-Farber Cancer Institute, Inc. v. Ono Pharmaceutical Co., 964 F.3d 1365 (Fed. Cir. 2020), decided July 14, 2020, is the most consequential joint-inventorship decision of the modern biotech era. Against the backdrop of a Nobel Prize and immunotherapy drugs that generate billions in annual revenue, the Federal Circuit affirmed an order adding two scientists, Dr. Gordon Freeman and Dr. Clive Wood, as co-inventors of six patents covering the PD-1/PD-L1 checkpoint blockade. The opinion is a working tutorial on what it takes to be a joint inventor and, just as important, what it does not take.

At a glance

• Case: Dana-Farber Cancer Institute, Inc. v. Ono Pharmaceutical Co., 964 F.3d 1365 (Fed. Cir. 2020), No. 19-2050
• Decided: July 14, 2020; panel of Judges Lourie, Newman, and Stoll, opinion by Judge Lourie; affirming the U.S. District Court for the District of Massachusetts after a bench trial
• Holding: Drs. Freeman and Wood were properly added as joint inventors under 35 U.S.C. § 256 because their significant contributions to the conception of the claimed inventions satisfied joint-inventorship standards, notwithstanding that they did not participate in every experiment, contribute to every claim, or make separately patentable contributions
• Status: Final; the Federal Circuit denied rehearing and the Supreme Court denied certiorari

The statutory frame: what makes a joint inventor

Inventorship is a question of who conceived the claimed invention. Conception is the touchstone: the formation in the mind of a definite and permanent idea of the complete and operative invention, as later reduced to practice. The governing standard traces to Burroughs Wellcome Co. v. Barr Laboratories, Inc., 40 F.3d 1223 (Fed. Cir. 1994), which anchors inventorship in conception rather than reduction to practice.

Joint inventorship is governed by 35 U.S.C. § 116, which is deliberately permissive. It provides that inventors may apply jointly even though they did not physically work together or at the same time, did not each make the same type or amount of contribution, and did not each contribute to the subject matter of every claim. Section 256 in turn allows a court to order correction of inventorship when a person has been erroneously omitted. To police the line between a true co-inventor and a mere helper, the Federal Circuit applies the three-part test of Pannu v. Iolab Corp., 155 F.3d 1344 (Fed. Cir. 1998): a putative inventor must contribute in some significant manner to the conception or reduction to practice of the invention, make a contribution that is not insignificant in quality when measured against the full invention, and do more than explain well-known concepts or the current state of the art.

The science and the dispute

The patents at issue claim methods of cancer treatment using antibodies that block the PD-1 receptor or its ligand PD-L1, thereby releasing a brake the immune system otherwise imposes on itself and unleashing T cells against tumors. This checkpoint-blockade mechanism is the scientific foundation of drugs such as nivolumab and pembrolizumab.

Dr. Tasuku Honjo of Kyoto University, who discovered PD-1 and later shared the 2018 Nobel Prize in Physiology or Medicine, was among the named inventors on patents assigned to Ono Pharmaceutical and licensed to Bristol-Myers Squibb. Dana-Farber sued under § 256, contending that its scientist Dr. Freeman and the former Genetics Institute scientist Dr. Wood had contributed significantly to the conception embodied in the claims and had been wrongly left off. The district court, after a bench trial, agreed and ordered them added. Ono, Honjo, and Bristol-Myers Squibb appealed.

The record credited a chain of contributions: Drs. Freeman and Wood’s discovery of the PD-L1 ligand, Dr. Wood’s finding that PD-1/PD-L1 binding inhibits the immune response, their joint work showing that anti-PD-1 and anti-PD-L1 antibodies can block that inhibitory signal, and Dr. Freeman’s immunohistochemistry experiments confirming PD-L1 expression across tumor types. The district court found these contributions significant to the conception of all six patents.

The court’s reasoning: collaboration is not disqualification

The Federal Circuit affirmed in full. Judge Lourie’s opinion rejected each of the appellants’ theories for why Freeman and Wood should not count.

First, the appellants argued that because some of Freeman and Wood’s contributions were published before the priority date, those contributions were part of the prior art and could not support inventorship. The court disagreed. Collaboration is the ordinary way science advances, and the mere fact that a contribution was later disclosed in a publication does not retroactively demote the contributor. A joint inventor need not demonstrate that their contribution was novel in isolation. The relevant question is whether the person contributed significantly to the conception of the claimed subject matter, not whether that contribution would have been independently patentable.

Second, the appellants urged that the contributions were too remote in time and too general, the sort of state-of-the-art background that Pannu excludes. The court read the record otherwise. The contributions here were not generic teachings of what any skilled scientist already knew; they were specific experimental findings about the PD-1/PD-L1 axis that fed directly into the conception of the claimed treatment methods.

Third, the appellants argued that the collaboration’s work was too speculative to count toward conception until Dr. Iwai’s October 2000 in vivo knockout-mouse experiments, which Freeman and Wood took no part in. The court rejected that as well. Conception is complete when an idea is definite and permanent enough that one of skill in the art could understand the invention, and an inventor need not know that the invention will work for its intended purpose, because verifying that it actually works is part of reduction to practice rather than conception. On the record, moreover, Dr. Iwai’s work came after Dr. Freeman had shown PD-L1 expression in human tumors. What conception of these method claims did depend on was knowing that the PD-1 receptor binds a ligand that inhibits the immune response, since without that there would be no reason to use anti-PD-1 antibodies against tumors at all, and that understanding drew materially on Freeman and Wood’s work. That collaborators did not sit in the same lab, run every assay, or appear on every claim did not undo their status, precisely the scenario § 116 was written to accommodate.

What the decision settled and unsettled

Dana-Farber did not announce a new test. Its significance lies in a forceful, high-stakes application of settled doctrine to a modern collaborative research setting. The opinion confirms that the § 116 factors are disjunctive shields against over-restrictive inventorship, that prior publication of a collaborator’s foundational findings is not a bar, and that a court sitting in equity under § 256 will follow the science where it leads even when billions in licensing value ride on the result.

Open questions

The decision leaves the hardest problems where they have always lived: in the facts. How much of a foundational discovery must feed the conception of a downstream method claim before its author becomes a co-inventor rather than a cited reference? Dana-Farber answers that on its record but supplies no bright line, and the boundary between a significant contribution to conception and background prior art will continue to be litigated collaboration by collaboration. The case also does not resolve how institutions should allocate ownership when co-inventors sit at different universities and companies, a downstream contract and policy problem the patent statute does not address. Finally, because each co-owner may license a jointly owned patent without the others’ consent absent an agreement, the practical consequences of a late inventorship correction remain formidable and largely a matter of private ordering.

Implications for inventors and businesses

• Map every contributor before filing. Reconstruct the conception story across labs and institutions and name inventors accurately. An omission corrected years later under § 256 can hand a new co-owner independent licensing rights.
• Do not assume publication erases inventorship. A collaborator’s earlier paper does not neutralize their contribution to a later claim. Treat foundational collaborators as potential inventors, not merely as citations.
• Paper the collaboration. Joint research agreements, assignment provisions, and clear records of who conceived what are the only reliable defense against inventorship surprises on high-value patents.
• Diligence acquired portfolios for inventorship risk. In life-sciences deals, unresolved co-inventor claims can undermine exclusivity and royalty structures. Price and allocate that risk before closing.

Frequently asked questions

Does a joint inventor have to contribute to every claim of a patent? No. Under 35 U.S.C. § 116, a person can be a joint inventor even if they did not contribute to the subject matter of every claim. A significant contribution to the conception of a single claim is enough to require naming that person as a co-inventor of the patent.

Can published research or collaboration defeat someone’s claim to be a joint inventor? Not by itself. The court rejected the argument that because certain contributions were publicly disclosed before the patented work, they could not count toward conception. Prior publication of a collaborator’s foundational findings does not automatically strip that collaborator of inventor status.

What is the practical risk of Dana-Farber for research institutions? Multi-lab collaborations on blockbuster inventions create real co-ownership exposure. Because each co-owner can independently license a patent, an omitted inventor added later under § 256 can unsettle exclusive-license and royalty arrangements worth billions.

Authorities and sources

• Dana-Farber Cancer Institute, Inc. v. Ono Pharmaceutical Co., 964 F.3d 1365 (Fed. Cir. 2020), No. 19-2050 (July 14, 2020), slip opinion (U.S. Court of Appeals for the Federal Circuit) and Google Scholar.
• 35 U.S.C. § 116 (joint inventors) and 35 U.S.C. § 256 (correction of named inventor).
• Pannu v. Iolab Corp., 155 F.3d 1344 (Fed. Cir. 1998) (three-part joint-inventorship test).
• Burroughs Wellcome Co. v. Barr Laboratories, Inc., 40 F.3d 1223 (Fed. Cir. 1994) (conception standard).
• Finnegan case analysis.
• National Law Review, “Dana-Farber v. Ono: Co-Inventorship Rules”.