There is no standing or lack of mootness requirement to challenge issued patent claims by filing a petition for inter partes review (IPR) in the U.S. Patent Office. Anyone other than the patent owner (and not otherwise barred by the estoppel provisions) can file a petition. But thanks to recent decisions by the U.S. Court of Appeals for the Federal Circuit (CAFC), we have clarity that both requirements must be met to appeal an adverse final written decision issued during that IPR, and we also have some guidance as to how these requirements will be determined in such cases.

In particular, last month’s precedential decision by the CAFC in the case of Momenta Pharmaceuticals v. Bristol-Myers Squibb (No. 2017-1694, Feb. 7, 2019) provides a clear line between the statutory right of any party other than the patent owner (and not otherwise barred by the estoppel provisions) to file a petition for IPR, and the additional Article III requirements to appeal an adverse final decision resulting from that proceeding. Relying on this distinction, the CAFC dismissed an appeal―from biotech company Momenta―of an IPR final written decision sustaining the patentability of Bristol-Myers Squibb’s claims covering its Orencia® (abatacept) biologic product. Because of evidence that Momenta had abandoned its development of an Orencia® biosimilar and no longer had “concrete plans” in this regard, the CAFC found that Momenta’s IPR appeal was barred by a lack of standing and for mootness.