Pre-AIA Patent Applications Filed Before but Published After the Priority Date of a Challenged Patent are “Printed Publications” for IPRs

On January 14, 2025, the Court of Appeals for the Federal Circuit (CAFC) issued a ruling in Lynk Labs, Inc. v. Samsung Electronics Co. Ltd., No. 23-2346, clarifying whether a patent application that is § 102(e)(1) prior art qualifies as a prior art printed publication in an IPR proceeding. The America Invents Act (AIA), passed by Congress in 2011, introduced inter partes review (IPR) as a post-grant procedure before the Patent Trial and Appeal Board (PTAB) at the United States Patent and Trademark Office (USPTO), replacing the previous inter partes reexamination process. IPR allows third parties to challenge the validity of one or more claims in a granted U.S. patent. Challenges in an IPR are restricted to grounds under §§ 102 or 103 and must be based on prior art consisting of patents or printed publications. A petition for IPR can be filed either nine months after the patent grant (or the issuance of a reissue patent) or, if a post-grant review is initiated, after the post-grant review concludes.

IPRs provide several advantages for petitioners, including a lower evidentiary burden. In an IPR, the petitioner must demonstrate that the challenged claims are unpatentable by a “preponderance of the evidence.” This is in contrast to federal district court invalidity proceedings, which require the higher standard of “clear and convincing evidence.” Additionally, IPRs typically offer a more cost-effective and quicker resolution compared to district court invalidity proceedings.

IPRs are authorized by 35 U.S.C. § 311(b): “petitioner in an inter partes review may request to cancel as unpatentable one or more claims of a patent only on a ground that could be raised under section 102 or 103 and only on the basis of prior art consisting of patents or printed publications.” The Samsung case stemmed from the PTAB’s decision regarding Samsung’s petition to institute an IPR of Lynk Labs’ U.S. Patent No. 10,687,400 (the ‘400 patent), which relates to light emitting diodes (LEDs) and LED drivers. Because the ‘400 patent’s priority date was prior to March 16, 2013, whether a reference qualifies as prior art is determined pursuant to pre-AIA § 102. In the petition, Samsung argued that the claims of the ‘400 patent were unpatentable based on U.S. Patent Publication No. 2004/0206970 of Martin (“Martin”). Martin, filed on April 16, 2003 (prior to the ‘400 patent's priority date of February 25, 2004), was published on October 21, 2004, but was subsequently abandoned. Section 102(e)(1) provides that “[a] person shall be entitled to a patent unless (e) the invention was described in (1) an application for patent, published under section 122(b), by another filed in the United States before the invention by the applicant for patent.” Martin qualifies as § 102(e)(1) art because although Martin published after the effective filing date of the ‘400 patent, Martin’s priority date was before the priority date of the ‘400 patent.

Lynk Labs contended that Martin should not be considered prior art to the ‘400 patent in an IPR. Specifically, Lynk Labs argued that: (1) the IPR petition presumes that Martin qualifies as prior art under § 102(e)(1); (2) Martin is not a patent because it was abandoned and never issued as a patent; and (3) Martin is not prior art because it is not a printed publication under § 311(b) because it was not publicly accessible before the priority date of the ‘400 patent, citing Samsung Elecs. Co. v. Infobridge Pte. Ltd., 929 F.3d 1363 (Fed. Cir. 2019) as support. The PTAB concluded that § 102(e)(1) prior art is properly asserted in an IPR, citing non-precedential Purdue Pharma L.P. v. Iancu, 767 Fed. App’x 918, 920-21, 926 (Fed. Cir. 2019), as well as a series of IPRs (where § 102(e)(1) prior art was available as prior art in an IPR) as persuasive authority and the Federal Circuit affirmed the PTAB decision.

In the opinion, the Federal Circuit found that the plain language of §§ 311(b) and 102(e)(1) supports treating a published patent application as a “printed publication” under § 311(b).

Regarding Lynk Labs’ assertion that historical context of § 311(b) supports that a published patent application of § 102(e)(1) should not be considered a “printed publication” in an IPR, the Federal Circuit concluded that historical context further supports the plain language interpretation of §§ 311(b) and 102(e)(1) discussed above.

Congress created procedures for ex parte reexamination of issued patents in 1980. Section 302 of the 1980 Patent Act provided that “any person . . . may file a request for reexamination . . . of a patent on the basis of any prior art cited under section 301,” where § 301 defines prior art as consisting of patents or printed publications. Congressional intent for limiting prior art to patents or printed publications was to include materials that are usually handled by patent examiners, and to exclude other invalidity grounds, such as public use and sales.

In 1999, Congress amended the Patent Act, establishing procedures for inter partes reexamination on the basis of any prior art cited under section 301 (i.e., patent or printed publication); providing for the publication of patent applications within 18 months of the priority date; and creating § 102(e)(1), which establishes a rule for when a patent application published under § 122(b) would be considered prior art.

The language of the 1980 and 1999 amendments to the Patent Act is consistent with the language in the AIA, which established the creation of IPR proceedings, replacing inter partes reexamination.

Lynk Labs argued that when Congress established published patent applications as prior art under § 102(e)(1) and also allowed inter partes reexaminations to be based solely on “printed publications,” it effectively referred to the legal term “printed publication” from old case law and carried over the case law’s interpretation of “printed publication” (“old soil”) to mean that a reference is publicly accessible. Lynk Labs contended that this historical context meant patent applications could never qualify as “printed publications.” The Federal Circuit disagreed, noting that “printed publications” includes published patent applications since published patent applications are publicly accessible. Lynk Labs further argued that a reference could only be considered a prior art printed publication if it was publicly accessible before the relevant date of the challenged patent (in this case, the priority date of the ‘400 patent). Based on this reasoning, Lynk Labs concluded that the term “printed publications” in § 311(b) excludes published patent applications treated as prior art under § 102(e)(1), since § 102(e)(1) does not require these applications to have been publicly accessible prior to the relevant date of the challenged patent.

Lynk Labs’ arguments were based on case law that predates the publication of patent applications, so these cases did not address published patent applications. Given that patent applications were not published when these cases were decided, the Federal Circuit concluded that it is incorrect to assert that patent applications can never qualify as “printed publications.” Lynk Labs also asserted that the case law concerning §§ 102(a) and 102(b) “printed publication[s]” established when a printed publication must be publicly accessible to be treated as prior art. The court was unpersuaded, finding that the timing of when a printed publication qualifies as prior art is not governed by the meaning of “printed publication,” but is instead governed by the statutory language of § 102. The language in § 102(e)(1) reflects Congress’s intent to give published patent applications a prior art effect that differs from the effect given to printed publications under § 102(a) and (b).

The court clarified when a published patent application can serve as a prior art reference in an IPR of a pre-AIA patent. Challenges based on § 102(e)(1) art are permitted based on the plain language of the statute, despite the fact that § 102(e)(1) refers to “an application for patent, published under section 122(b)” and does not specifically refer to the published application as a “printed publication” as recited in § 311(b). In addition, published patent applications may serve as prior art in an IPR as of the priority date of the published patent application. This is consistent with post-AIA § 102(a)(2), wherein a published patent application is prior art if it was effectively filed before the effective filing date of the challenged patent. One key difference to keep in mind in determining the priority date (“date of invention”) under pre-AIA § 102 and post-AIA § 102 is that under pre-AIA § 102 foreign priority did not count. Pursuant to post-AIA § 102, an application’s effective filing date is the earliest application date, which includes the filing date of the earliest provisional, nonprovisional, international (PCT), or foreign patent application.

Stites & Harbison, PLLC’s full-service Intellectual Property & Technology Group regularly assists clients in the acquisition, management, licensing, and litigation of patents, copyrights, trademarks, and trade secrets. For questions, comments, or assistance with any intellectual property-related matters, please contact the authors or any of the other agents or attorneys in the IPT group.