This is a question that every patent attorney faces during their career.  Who contributed to the invention covering a product can become contentious, particularly in the pharmaceutical context where successes are few and far between.  The Federal Circuit addressed the issue of when a suggestion amounts to a contribution to conception of an invention in the recent decision of Cumberland Pharmaceuticals Inc. v. Mylan Inc., No. 16-1155 (Fed. Cir. Jan. 24, 2017).

Background Facts

The patent at issue, US 8,399,445 B2, covers methods of treating acetaminophen overdose with stable acetylcysteine compositions substantially free of chelating agents.  Mylan challenged the patent under 35 USC 102(f) arguing that the listed inventor derived the invention from a suggestion of the Food and Drug Administration (FDA).

Cumberland sought FDA approval of an acetylcysteine formulation that contained the chelating agent EDTA.  While reviewing Cumberland’s New Drug Application, the FDA instructed Cumberland to provide scientific and regulatory justification for including the chelating agent EDTA in the formulation since the amount included was non-trivial.  Based on the understanding in the prior art that a chelating agent was needed to stabilize the drug in the formulation, Cumberland responded to the FDA’s request that lowering or removing EDTA would raise questions about the safety and efficacy of the product.

The inventor testified that shortly after this exchange, he had the idea of testing the stability of the formulation without EDTA.  As part of a post-marketing commitment, Cumberland conducted stability studies and found that not only was EDTA not required for a stable solution, but that a stable solution could be prepared without any chelating agent, which finding formed the basis of the claims in the patent.

The Decision

Did the FDA’s request to justify the chelating agent EDTA in the formulation amount to a contribution to the conception of the invention? The Court held that the FDA did not contribute to the conception of the invention as claimed, i.e. an acetylcysteine formulation not only without EDTA but without any chelator.

Conception requires that “the inventor has a specific, settled idea, a particular solution to the problem at hand, not just a general goal or research plan he hopes to pursue.” See Burroughs Wellcome Co. v. Barr Labs., Inc., 40 F.3d 1223, 1228 (Fed. Cir. 1994).  According to the Federal Circuit, giving a general research direction does not amount to inventorship.  The Court found that the FDA’s request was “not the same as a suggestion to remove it [EDTA], let alone to remove it and not replace it with another chelating agent.”  Thus, the FDA did not contribute to the conception of the invention as claimed.


Because suggestions rising to the level of inventive contributions need to be specific and concrete, it is advisable that counsel proactively interview all potential contributors to determine how an invention was conceived and by whom. It is worth being  overinclusive in these interviews, talking to both supervisors and bench-level scientists independently, and asking for details about particular difficulties discovered and overcome, even to the point of asking the same question in different ways. If done properly, openness and fairness in the process will protect the patentee and will help to make the potential contributors believe in the result.

Further, when beginning an interview process, it is important not to underestimate the importance of inventorship to a scientist. A contributor who is left off an invention disclosure can cause strife while inside the company or from the outside through invalidity and derivation proceedings or by asserting an ownership interest. In the boom and bust pharmaceutical industry, ex-employee scientists who become disgruntled in tight job markets may use inventorship as a way to “get back,” often at the most inconvenient times for a patentee, e.g. at market launch or during licensing negotiations. To be sure, some comfort can be taken from the fact that derivation challenges of post-AIA applications must be filed within one year of the application’s publication and that in light of the long time periods needed for preclinical and clinical testing, a contributor would have to challenge at a time, potentially long before the importance of the invention is fully understood.  However, the Cumberland case serves to remind that it is far better to attempt to understand and address any potential inventership problems at the outset.