Topwire LLC v. SAMSUNG ELECTRONICS CO., LTD. et al.

Case Overview and Background

This patent infringement lawsuit pits Topwire LLC, a recently formed Texas-based entity, against global technology and manufacturing giant Samsung Electronics Co., Ltd. and its US subsidiary. Formed in February 2025, Topwire LLC appears to be a non-practicing entity (NPE), also known as a patent assertion entity (PAE), as its primary activity is patent litigation. The entity acquired the patent-in-suit in March 2025 from the sole inventor. Samsung is a South Korean multinational corporation and a major manufacturer of a vast array of consumer and industrial electronics, including semiconductors and mobile devices. The lawsuit accuses Samsung of infringing a single patent, U.S. Patent No. 9,859,202, through its sale of certain Galaxy 10-series smartphones and later models that incorporate "double-layered logic boards with two substrates." The '202 patent, titled "Semiconductor structure with a through-silicon via (TSV) for separating and electrically connecting two layered packaging substrates," generally relates to a method for creating vertical interconnections in stacked semiconductor packages.

The case was filed on December 1, 2025, in the U.S. District Court for the Eastern District of Texas and is assigned to Judge Rodney Gilstrap, one of the most active patent judges in the country. This venue is historically favored by patent plaintiffs, particularly NPEs, due to its local rules and judicial expertise in patent matters, which can lead to faster case resolutions and a perceived plaintiff-friendly environment. Though its dominance has been challenged by other districts and changes in venue law, the Eastern District of Texas remains a top venue for patent litigation. The case is notable as it represents Topwire's inaugural litigation campaign, which also includes a parallel lawsuit filed the same day against Apple in the Western District of Texas asserting the same patent.

This litigation reflects a broader trend of NPEs targeting major technology companies over complex semiconductor and electronics manufacturing patents. Adding to the case's significance, Samsung has already initiated a proceeding at the Patent Trial and Appeal Board (PTAB), filing a petition for inter partes review (IPR) on March 31, 2026, challenging the validity of the '202 patent. This dual-front battle—in district court and at the PTAB—is a common strategy in high-stakes patent disputes, where accused infringers seek to invalidate the asserted patent at the U.S. Patent and Trademark Office while simultaneously defending against infringement claims in court. The outcome of both the district court case and the IPR will be closely watched within the semiconductor and mobile device industries.

Legal Developments and Case Status

As of May 2026, the patent infringement lawsuit initiated by Topwire LLC against Samsung remains in its early stages in the Eastern District of Texas, while a parallel challenge to the patent's validity is pending before the Patent Trial and Appeal Board (PTAB).

Key events in the litigation have unfolded chronologically:

• 2025-12-01: Complaint Filed
  Topwire LLC filed its complaint against Samsung Electronics Co., Ltd. and Samsung Electronics America, Inc., alleging infringement of U.S. Patent No. 9,859,202. The suit claims that Samsung's Galaxy 10-series smartphones and later models, which feature "double-layered logic boards," infringe upon Topwire's patent for semiconductor packaging technology. The case was assigned to Judge Rodney Gilstrap, a prominent figure in U.S. patent litigation.

• 2026-02-18 (approx.): Motion to Transfer Venue
  On or around this date, Samsung filed a motion to transfer the case from the Eastern District of Texas to the District of New Jersey for convenience. In its motion, Samsung highlighted that Topwire's manager, patent attorney Robert Katz, had previously been involved as counsel in at least two other patent suits against Samsung concerning similar technologies. The disposition of this motion has not yet been reported.

• 2026-03-23: Samsung Files Answer
  Samsung filed its answer to Topwire's complaint, denying the allegations of infringement and likely asserting various affirmative defenses and counterclaims, which typically include non-infringement and patent invalidity.

• 2026-03-31: Inter Partes Review (IPR) Petition Filed
  In a significant move, Samsung filed a petition for inter partes review with the USPTO's Patent Trial and Appeal Board (PTAB), challenging the validity of the '202 patent. This proceeding, assigned case number IPR2026-00324, allows for an administrative review of the patent's claims based on prior art. The IPR is currently in a "Pending" status, awaiting a decision from the PTAB on whether to institute a formal review.

The filing of the IPR petition is a critical strategic development. Accused infringers frequently use IPRs to challenge patent validity in a forum often considered more favorable than district courts. If the PTAB institutes the IPR and ultimately finds the patent claims invalid, it could resolve the district court litigation in Samsung's favor.

Given the early stage of the case and the pending IPR, no substantive pre-trial motions, such as a motion to stay pending the IPR or motions for summary judgment, have been ruled upon. Similarly, the case has not yet reached key milestones like a Markman hearing for claim construction. The current posture of the case is active, with the district court proceedings likely to be influenced heavily by the PTAB's forthcoming institution decision on the IPR petition.

Counsel for Plaintiff Topwire LLC

Based on a review of the initial complaint and reports from legal news outlets, the following attorneys and firms have appeared on behalf of the plaintiff, Topwire LLC.

Lead Counsel

• Name: Stamatios Stamoulis

  • Role: Lead Counsel
  • Firm: Stamoulis & Weinblatt LLC
  • Office Location: Wilmington, Delaware
  • Note: Mr. Stamoulis has over two decades of experience in intellectual property litigation, having practiced at major international firms like O'Melveny & Myers and Fish & Richardson before co-founding his own firm, which frequently represents patent plaintiffs in federal courts, including the Eastern District of Texas and the District of Delaware.

• Name: Richard C. Weinblatt

  • Role: Lead Counsel
  • Firm: Stamoulis & Weinblatt LLC
  • Office Location: Wilmington, Delaware
  • Note: Mr. Weinblatt has extensive experience in patent litigation and appeals, previously practicing at Fish & Richardson, and has argued numerous times before the U.S. Court of Appeals for the Federal Circuit.

Local Counsel

• Name: Wesley T. Spangler
  • Role: Local Counsel
  • Firm: Spangler Law PC
  • Office Location: Longview, Texas
  • Note: Mr. Spangler is an experienced East Texas litigator who frequently serves as local counsel for out-of-state firms in patent cases filed in the district.

Counsel for Defendant Samsung Electronics

Based on court filings and legal reporting, Samsung has retained a team from the law firm Gillam & Smith LLP to serve as local counsel in this matter. Further appearances by national counsel are expected as the case progresses.

Local Counsel

• Name: Melissa Richards Smith
  • Role: Local Counsel
  • Firm: Gillam & Smith, LLP
  • Office Location: Marshall, Texas
  • Note: Ms. Smith is a partner at a well-regarded East Texas firm and frequently acts as local counsel for major technology companies, including Samsung, in patent cases before the Eastern District of Texas.

It is common practice for Samsung to engage prominent national law firms with deep expertise in high-stakes patent litigation to lead its defense. Firms such as DLA Piper, Kirkland & Ellis LLP, and Quinn Emanuel Urquhart & Sullivan, LLP have represented Samsung in other recent, significant patent disputes, including cases in the Eastern District of Texas. Announcements of lead counsel from a national firm are anticipated as the case moves beyond the initial pleading stage.

There is no information in the public record to suggest any in-house counsel from Samsung has formally appeared in the case at this time, though they are undoubtedly managing the litigation internally.