A claim is said to be anticipated when a single prior art reference discloses, either expressly or inherently, each and every limitation of the claim. But what happens when a prior art reference discloses some aspects of the claimed invention and incorporates by reference additional prior art references that disclose other aspects of the claimed invention? According to the Federal Circuit, the prior art reference together with its incorporated references can anticipate the claims. Arbutus Biopharma Corp. v. ModernaTX, Inc., No. 2020-1183, 2023 WL 2876820 (Fed. Cir. Apr. 11, 2023).
Arbutus Biopharma Corporation (Arbutus) is the owner of U.S. Patent No. 9,404,127 (the ’127 patent), which is said to provide “novel, stable lipid particles having a non-lamellar structure and comprising one or more active agents or therapeutic agents.” ’127 patent at abstract. The ’127 patent states that “[t]he present invention is based, in part, upon the surprising discovery that by controlling the lipid composition of a [stable nucleic acid-lipid particles (SNALP)] formulation as well as the formation process used to prepare the SNALP formulation, a novel non-lamellar lipid nanoparticle (i.e., SNALP) can be produced.” Id. at col. 8, lines 51-55. Claim 1 of the ’127 patent is as follows:
1. A composition comprising:
a plurality of nucleic acid-lipid particles, wherein each particle in the plurality of particles comprises:
(a) a nucleic acid;
(b) a cationic lipid;
(c) a non-cationic lipid; and
(d) a conjugated lipid that inhibits aggregation of particles,
wherein at least about 95% of the particles in the plurality of particles have a non-lamellar morphology.
According to the ’127 patent, lipid particles having a non-lamellar morphology (which the ’127 patent defines as having a non-bilayer structure) can be formed from specific amounts of cationic lipids, non-cationic lipids, and lipid conjugates and prepared using the Direct Dilution Method (DDM). Id. at col. 8, lines 55-62. The ’127 patent incorporates by reference U.S. Patent Publication No. 2007/0042031 (the ’031 publication) “in its entirety for all purposes” for the disclosure of the DDM and the apparatuses for carrying out the DDM. Id. at col. 104, lines 32-37.
Moderna filed a petition for inter partes review, arguing that Arbutus’ earlier patent – U.S. Patent No. 8,058,069 (the ’069 patent) – anticipated the claims of the ’127 patent. The ’069 patent, like the ’127 patent, discloses SNALPs and incorporates by reference “in its entirety for all purposes” the ’031 publication for the “processes and the apparatuses for carrying out these direct dilution processes.” ’069 patent at col. 59, lines 12-16. The PTAB ruled that the ’127 patent’s claims were invalid as anticipated and determined that the Morphology Limitation of claim 1 was inherently anticipated by the ’069 patent and that patent’s incorporated references “because the Morphology Limitation is an inherent property or natural result of the disclosures.” Arbutus, 2023 WL 2876820, at *3.
On appeal, the Federal Circuit affirmed the PTAB’s decision. The court acknowledged that the ’069 patent does not explicitly teach the Morphology Limitation (id. at *4) but found that claim 1’s Morphology Limitation is inherently anticipated by the ’069 patent and that patent’s incorporated references. Id. at *7. According to the court, “[t]he ‘critical question’ for inherent anticipation is ‘whether the [prior art] patent sufficiently describes and enables one or more embodiments – whatever the settings of their operational features – that necessarily include or result in the subject matter of [the] limitation.’” Id. at *5 (citing Toro Co. v. Deere & Co., 355 F.3d 1313, 1321 (Fed. Cir. 2004)). Regarding incorporation by reference, the court stated that “[w]hen a reference or material from various documents is incorporated, they are ‘effectively part of the host document as if [they] were explicitly contained therein.’” Arbutus, 2023 WL 2876820, at *4 (citing Advanced Display Sys., Inc. v. Kent State Univ., 212 F.3d 1272, 1282 (Fed. Cir. 2000)). In reaching its decision that the PTAB did not err in finding that the Morphology Limitation was inherently anticipated, the court found that the ’127 patent and the ’069 patent disclose the same formulations, the ’127 patent and the ’069 patent both incorporate by reference the ’031 publication for that reference’s disclosure of the DDM, and the DDM process described in the ’031 publication “would naturally result in a composition having the claimed morphological property.” Arbutus, 2023 WL 2876820, at *5.
Anticipation requires a showing that a single prior art reference provides an express or inherent disclosure of each and every claim feature. In the Arbutus decision, however, it was a combination of references – the ’069 patent and those references that were incorporated therein – that were found to anticipate the claims at issue. Without this incorporation by reference, the issue in Arbutus may have come down to obviousness (e.g., a combination of the ’069 patent and the ’031 publication), which has a different burden of proof. Additionally, the incorporation of the ’031 publication’s subject matter into both the patent at issue and the prior art reference was a key factor in the inherency finding. Although patent applicants often incorporate subject matter by reference into a patent application in an attempt to provide support for the claimed subject matter, the Arbutus decision highlights a potential pitfall in doing so.
 The Patent Trial and Appeal Board (PTAB) and Federal Circuit referred to the italicized claim feature as the “Morphology Limitation.”