United States: SK Hynix Sues Longhorn IP And Two Of Its "Portfolio" Entities

SK hynix ( 3:22-cv-03915) has filed a single Northern District of California action against monetization firm Longhorn IP LLC and two of its "portfolio" entities, Hamilcar Barca IP LLC and Trenchant Blade Technologies LLC, seeking declaratory judgments of noninfringement of seven patents. The plaintiff alleges receipt of multiple letters from the plaintiffs, beginning in May 2020, giving rise to jurisdiction over the dispute, by which SK hynix seeks to clear a wide array of products, including image sensors, integrated circuit devices, and memory products, from the Longhorn IP accusations of infringement. This litigation was foreshadowed, at least in part, by a letter attached to an earlier DJ complaint against Longhorn IP, revealing its "intent to license the patent portfolio [of Trenchant] to other companies, including Samsung, Micron, SK hynix, Global Foundries, UMC and SMIC".

The new complaint is organized around "the Hamilcar Patent Portfolio" (8,086,938; 8,669,619; 8,848,462; 9,147,664; 9,379,079), originating with MediaTek, and "the Trenchant Blade Patent Portfolio" (7,056,821; 7,494,846), originating with TSMC. On Longhorn IP's website, Hamilcar Barca IP is identified as holding assets in the "Technology Areas" of "Semiconductor devices manufacturing technology, Microprocessors, Power saving", but currently available USPTO records do not reflect the entity's ownership of any US patent assets. SK hynix pleads that the patents-in-suit were mentioned in letters, claim charts, and other interactions between March and June 2022.

In two transactions (here and here) dated in May 2021—a couple of months after MediaTek separately transferred three patents to SK hynix—MediaTek assigned 18 US patent assets to Fortieth Floor LLC, an entity associated with monetization firm Steger IP, formed by Steven Steger after his departure, around July 2018, from Global IP Law Group, LLC. As noted, a transfer of these assets away from Fortieth Floor (to Hamilcar Barca IP or elsewhere), has been recorded. SK hynix seeks declaratory judgments that its memory products using a "flip-chip configuration with similar bump patterns" do not infringe the '079 patent; its memory products with Pseudo Open Drain (POD) signaling and architecture, the '462 patent; its memory products supporting Serial ATA Revision 3.x interface and later, the '938 patent; its "surface-mounted" memory devices, the '664 patent; and its image sensors and related devices containing a multi-layer CESL structure, the '619 patent.

The '821 and '846 patents were assigned from TSMC to Trenchant in March 24, 2020 under circumstances involving another Longhorn IP plaintiff, Katana Silicon Technologies LLC. To trace the assertions and subsequent patent assignments leading to Trenchant's portfolio pickup, see "Intel Also DJs Longhorn IP and Trenchant Blade in the Northern District of California" (May 2021). Suing that month, Intel attached to its complaint the letter laying out Trenchant's planned targets (noted above), with the Trenchant campaign itself having kicked off roughly six months earlier when Samsung filed its own DJ complaint. In both disputes, the DJ complaint was filed in the Northern District of California, Trenchant responding with an affirmative suit filed against each, Samsung in January 2021 and Intel in May 2021, in the Western District of Texas.

SK hynix seeks declaratory judgments that its products and fabrication technologies, including integrated circuit devices made using the Hynix 21 nm process node, do not infringe the '821 patent and that its products and fabrication technologies, including integrated circuit devices made using the TSV manufacturing process, do not infringe the '846 patent, as Longhorn IP and Hamilcar Barca IP have apparently alleged. Hamilcar Barca IP does not appear to have asserted any patents in litigation to date.

Litigation between Trenchant and both Intel and Samsung has now ended, Longhorn IP announcing just last month the end, under confidential terms, of its disputes with Samsung. Longhorn IP, however, does have other open matters, including a dispute with GlobalFoundries, filed by Katana, and a set of disputes with Micron, one filed by Katana in March 2022 in the Western District of Texas and another filed by Micron in early June 2022 in Idaho state court (for bad faith patent assertion) in June 2022, both now in Idaho federal court. Another Longhorn IP "portfolio" plaintiff, L2 Mobile Technologies LLC, has also just ended US litigation against each of Ford (background here) and Alphabet (Google) (here), while a German counterpart has reportedly just sued Nissan there.

Former Acacia Research Corporation executives Christian ("Chris") Dubuc and Khaled Fekih-Romdhane formed Longhorn IP in Texas back in April 2016. In March 2019, the two filed amendments for various controlled Texas entities—including for Longhorn IP—to shift the identified members from themselves as individuals to separate corporations that each person formed in Texas in May 2016: Taijitu Ventures Inc. (with Dubuc identified as its president and director) and Tanit Ventures Inc. (with Fekih-Romdhane so identified). Dubuc and Fekih-Romdhane later parted ways. Dubuc changed the name of Taijitu Ventures to Harfang IP Investment Corp, while other Texas state filings vest full control in Longhorn IP and its "portfolio" entities in Fekih-Romdhane alone (through Tanit Ventures).

Those "portfolio" entities include several others, beyond Harmilcar Barca IP, Katana, L2 Mobile, and Trenchant Blade, among them Carthage Silicon Innovations LLC, a Texas entity that holds a portfolio that includes patents the original development work for which was conducted at . . . SK hynix. 7/8, Northern District of California.

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