The Federal Circuit issued a precedential opinion in Lynk Labs, Inc. v. Samsung Electronics Co., Ltd. on January 14, 2025. Preceding the opinion, the Patent Trial and Appeal Board issued a final written decision finding claims 7-13 and 15-17 of U.S. Patent No. 10,687,400 (“the ’400 patent”) unpatentable in IPR2022-00149, and Lynk Labs appealed. The Federal Circuit affirmed the PTAB’s final decision.

The ’400 Patent describes light emitting diodes (LEDs), LED drivers, AC driven LEDs, LED circuits, and AC drive circuits and methods. The earliest effective filing date of the ’400 Patent is February 25, 2004. Both Lynk Labs and Samsung agreed that the pre-Leahy Smith America Invents Act (“AIA”) law applied given the filing date of the ’400 Patent.

The PTAB found the claims of the ’400 Patent unpatentable in view of U.S. Patent Application Publication No. 2004/0206970 (“Martin”). Martin was filed on April 16, 2003, before the earliest effective filing date of the ’400 Patent on February 25, 2004, but Martin was not published until October 21, 2004, after the ’400 Patent was filed. According to Lynk Labs on appeal, Martin was not available to the public before the earliest effective filing date of the ’400 Patent and, for that reason, not prior art in the IPR2022-00149 matter.

35 U.S.C. § 311(b) states that a petitioner in an IPR may request to cancel 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.”

Lynk Labs argued on appeal that the term “printed publication” in § 311(b) should be interpreted in light of its historical context and prior case law. According to Lynk Labs, a published patent application should be considered prior art only from its publication date in an IPR proceeding, not from its filing date under 35 U.S.C. § 102(e)(1). Lynk Labs referred to case law interpreting “printed publication” to mean references that were fully accessible to the public before the critical date. Lynk Labs also cited cases that addressed printed publications like books and articles, arguing that these cases established a precedent that patent applications could not be considered “printed publications” until they were publicly accessible.

Samsung identified that § 102(e)(1) explicitly states that a published patent application is prior art as of its filing date. In doing so, Congress created a special rule for published patent applications in § 102(e)(1), to treat a published patent application as prior art from its filing date. Congress also expressly distinguished published patent applications under § 102(e)(1) from other types of printed publications that require public accessibility. Samsung argued that treating published patent applications as prior art as of their effective filing date is consistent with Congress's purpose in IPR proceedings and § 311(b).

The Federal Circuit sided with Samsung and held that published patent applications are prior art in IPR proceedings as of their filing date under 35 U.S.C. § 102(e)(1), particularly in IPR proceedings in which pre-AIA law applies. The same can could be expected with respect to the earliest availability of prior art patents under 35 U.S.C. § 102(e)(2).