“Inherently obvious.” Is that an oxymoron? Perhaps, but it's a reality for patent practitioners.
For years, it was settled case law that inherency belonged in an anticipation analysis but not an obviousness one. “That which may be inherent is not necessarily known; obviousness cannot be predicated on what is unknown.” In re Spormann, 363 F.2d 444 (CCPA 1966).
Anticipation focuses on what is disclosed in the prior art. Thus, a prior art disclosure may inherently disclose a claim element even where a person of ordinary skill in the art would not have recognized that inherent element at the time of invention. See, e.g., Schering Corp. v. Geneva Pharms., 339 F.3d 1373 (Fed. Cir. 2003).
Then the courts started accepting that inherency may supply a missing claim limitation in an obviousness analysis, though with the caveats that use of inherency in obviousness “must be carefully circumscribed” and the limitation must be the “natural result” of the combination of prior art elements. See, e.g., PAR Pharms. v. TWI Pharms., 773 F.3d 1186 (Fed. Cir. 2014). This modern trend can be traced to the 2011 Federal Circuit decision In re Kao, 639 F.3d 1057 (Fed. Cir. 2011).
In Kao, the court held that the claimed formulation was obvious, and the specified food effect was an inherent property that did not render the claimed formulation nonobvious. See also Santarus, Inc. v. Par Pharms., Inc., 694 F.3d 1344 (Fed. Cir. 2012) (holding that the claims were obvious based on an inherent property of the claimed formulation). Using language very similar to an inherent anticipation analysis language, the court in LBT IP I LLC v. Apple Inc., 2023 U.S. App. LEXIS 14376 (Fed. Cir. June 9, 2023), stated:
“[T]o rely on inherency to establish the existence of a claim limitation in the prior art in an obviousness analysis,” Apple must show the activation/reactivation limitation is “necessarily present” or “the natural results of the combination of elements explicitly disclosed by the prior art.” . . . Mr. Andrews' testimony failed to meet this standard for inherent disclosure.
Id. at *8-9.
Obviousness focuses on the knowledge of a person of ordinary skill in the art at the time of the invention. In Honeywell Int'l Inc. v. Mexichem Amanco Holding S.A., 867 F.3d 1348 (Fed. Cir. 2017), the court explained that “all properties of a composition are inherent,” and thus when considering the obviousness of a composition what matters is whether its properties are known and expected. Id. at 1355. This tension between inherency (which allows for later recognition) versus obviousness (in which hindsight is forbidden) has led to blurry reasoning in applying inherency in an obviousness analysis, but it is an argument raised regularly by patent challengers so one patent owners must prepare for. So far, it is usually a tough standard to meet. Below are two recent examples, one from district court and one from the Patent Trial and Appeal Board (“the Board”).
District Court
In Bausch Health Ir. Ltd. v. Padagis Isr. Pharms. Ltd., 2022 U.S. Dist. LEXIS 216602 (D. NJ Dec. 1, 2022), the limitation at issue read: “wherein the composition . . . is capable of providing synergistic efficacy and synergistic reduction of at least an adverse event selected from the group consisting of itching, burning, and stinging in said treating.”
According to the district court, this was not obvious because the patent challenger (Padagis) did not demonstrate “that the claimed synergy limitations are properties of the composition or treatment method that would have been reasonably expected by a POSA as of the Priority Date. The significance of this determination is that Padagis has failed to demonstrate that the synergy limitations of the combination patent claims at issue are inherent and obvious.” Id. at *100-101.
PTAB
In BTC Corp. v. TG Biotech Co., Ltd., IPR2022-00998, Paper 44 (P.T.A.B. Nov. 13, 2023), Petitioner asserted that the concentrations disclosed in the prior art and experimental reports rendered the claimed concentrations inherently obvious.
The PTAB found that Petitioner did not show claims unpatentable because Petitioner's evidence failed to show that the prior art necessarily resulted in the claimed concentration. The experimental data was rejected because it deviated from the prior art protocols and used an impure DB standard made the results unreliable.
Conclusion
The Federal Circuit repeatedly stated that inherent obviousness is a narrow doctrine. An inherent limitation must necessarily be present in the combination of references. It is not enough to merely show that it is likely to be present. See Pers. Web Techs., LLC v. Apple, Inc., 917 F.3d 1376 (Fed. Cir. 2019); LBT IP I LLC v. Apple Inc., 2023 U.S. App. LEXIS 14376 (Fed. Cir. June 9, 2023).
Moreover, inherent properties of a new combination are only unpatentable if those properties were not unexpected at the time of the invention. Compare Allergan, Inc. v. Sandoz, Inc., 726 F.3d 1286 (Fed. Cir. 2013) (unexpected benefits not inherently obvious) Acorda Therapeutics, Inc. v. Roxane Labs., Inc., 903 F.3d 1310 (Fed. Cir. 2018) (expected properties may be inherently obvious). But measurements or functional limitations that are not unexpected and/or do not add to the novelty of the claimed invention may be obvious. See In re Couvaras, 70 F.4th 1374 (Fed. Cir. 2023), where the Federal Circuit upheld an obviousness rejection because “”[n]ewly discovered results of known processes directed to the same purpose are not patentable because such results are inherent.”
Patent owners should beware of limitations that can be cast as an “inherent property” and thus lacking patentable weight. If a challenger shows a property is inherent, “there is no question of a reasonable expectation of success in achieving [the property].” Hospira, Inc. v. Fresenius Kabi USA, LLC, 946 F.3d 1322, 1332 (Fed. Cir. 2020). “To hold otherwise would allow any formulation — no matter how obvious — to become patentable merely by testing and claiming an inherent property.” Santarus, Inc. v. Par Pharm. Inc., 694 F.3d 1344, 1354 (Fed. Cir. 2012).
Patent owners are reminded to challenge any unsupported conclusions or reliance on only common sense. See SSI Techs., LLC v. Dongguan Zhengyang Elec. Mech. Ltd., 2024 U.S. Dist. LEXIS 93391, *19-20 (W.D. Wis. May 23, 2024) (“Fourth, a party must meet a high standard to use an inherent disclosure to establish obviousness, PAR Pharm., Inc. v. TWI Pharms., Inc., 773 F.3d 1186, 1195-96 (Fed. Cir. 2014), and Ganssle's superficial explanation of the purported inherent disclosure of a chimney in Clayton doesn't meet it. . . . Conclusory assertions about obviousness like Ganssle's are not enough to survive summary judgment.”).
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