Lynk Labs, Inc. v. Samsung Electronics Co., Ltd., No. 2023-2346, 2025 WL 85559 (Fed. Cir. Jan. 14, 2025)
In Lynk Labs, Inc. v. Samsung Electronics Co., Ltd., the Federal Circuit affirmed a decision by the Patent Trial and Appeal Board (PTAB) that found that a patent application filed before the priority date of Lynk Lab’s patent—but published after—could serve as prior art in an inter partes review (IPR).
Lynk Labs owns U.S. Patent No. 10,687,400 (“the ‘400 patent”) which “generally relates to light emitting diodes (‘LEDs’) and LED drivers.” Samsung Electronics Co., Ltd. (“Samsung”) filed a petition for IPR of the ‘400 patent in 2021, challenging the patent on grounds of obviousness. The challenge relied on a patent application that was ultimately abandoned: U.S. Patent Application Publication No. 2004/0206970 (“Martin”).
Martin was filed on April 16, 2003, predating the February 25, 2004 priority date of the ‘400 patent. However, Martin wasn’t published until October 21, 2004—almost eight months to the date after the priority date of the ‘400 patent.
The PTAB determined that Martin’s filing date, not its publication date, controlled when it became printed publication prior art. Lynk Labs appealed this decision, arguing that Martin could not serve as prior art in an IPR because it did not become publicly accessible until after its publication date, even though its filing date preceded the priority date of the ‘400 patent. On January 14, 2025, the Federal Circuit affirmed the PTAB’s decision.
Key Legal Framework
Section 311(b) provides that in an IPR, the petitioner may only challenge 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.” Pre-AIA section 102, which applies to patents filed before March 16, 2013, provides for multiple categories of prior art. Case law dealing with section 102 prior art has consistently held that a printed publication must have been “sufficiently accessible to the public interested in the art before the critical date.” Voter Verified, Inc. v. Premier Election Sols., Inc., 698 F.3d 1374, 1380 (Fed. Cir. 2012).
In its brief on appeal, Lynk Labs contended that statutory language in pre-AIA § 102 “makes clear” that “printed publication[s]” and “application[s] for patent” are distinct terms with distinct meanings. However, the Court emphasized that pre-AIA section 102(e) provides a special rule for patent applications, allowing published patent applications to qualify as prior art and render an invention unpatentable if the application was filed before the priority date of the challenged patent. This is true even if the patent application does not result in an issued patent. The Court rejected Lynk Labs’ argument, noting that published patent applications are a type of printed publication and may serve as prior art in an IPR challenge.
Lynk Labs also argued that Congress’s use of the phrase “printed publication” in section 311(b) means that Congress intended to transplant the judicial interpretation of “printed publication” into the statute. To support this, they pointed to case law which held that a patent application can never be considered a “printed publication.” The Court noted that the cases cited in support of this argument were decided before patent applications were published at all—publication of patent applications only became routine after a 1999 amendment to the AIPA, which required most patent applications to be published 18 months after filing.
Additionally, Lynk Labs contended that “printed publications” can only be considered prior art if they were publicly accessible before the priority date of the challenged patent. In other words, they argued that the application must have been published before the filing of the challenged patent. However, the Court relied on the language of section 102(e)(1) to reject this argument, noting that “[b]y its explicit terms, [section 102(e)(1)] bars patentability based on a published application if that application was filed before the invention.”
What does this mean?
Since patent applications can serve as prior art as of their publication date for challenges to pre-AIA patents, patent owners must conduct thorough prior art searches that include not only issued patents but also published applications, regardless of whether they resulted in issued patents. Failure to account for those applications could leave a patent vulnerable to invalidation on obviousness grounds. Patent owners should consult experienced counsel to ensure they are fully prepared for potential IPR challenges, especially when navigating complex prior art issues like those raised in Lynk Labs.