Liberty Mutual and Safeco are facing a patent infringement suit over how Safeco handles electronic documents.
The complaint, filed on May 15, 2026 in the US District Court for the Eastern District of Texas, Marshall Division, was brought by Lone Star Document Management. It names Liberty Mutual Group, Liberty Mutual Insurance Company and Safeco Insurance Company of America as defendants.
At the heart of the case is U.S. Patent No. 6,918,082, titled "Electronic Document Proofing System." The patent issued in July 2005 from an application the inventors filed in December 1998. Lone Star says it owns the patent and the right to sue over it.
The complaint alleges Safeco directly infringed claim 16 by "selling, offering to sell, making, using, and causing to be used Safeco systems, including one or more hardware and software products for content management and related services." Lone Star calls them the "Accused Instrumentalities."
According to the filing, claim 16 covers a system that stores portable-format electronic documents alongside a proofer identifier, takes in comments tied to each document, and pulls up the document and its comments for simultaneous display so a reviewer can work through both at once. The patent, Lone Star says, addressed a 1990s problem: at the time, swapping electronic files between a creator and a proofreader "often necessitates that both parties use the exact same software version, often running on the same computer operating system."
The complaint also alleges Safeco has known about the patent for years. Lone Star says it sent Safeco a letter dated January 26, 2017, delivered by FedEx the next day, offering a license. According to the filing, Safeco has had knowledge of the patent since at least January 27, 2017, and Liberty Group and Liberty Insurance gained the same knowledge from Safeco.
Lone Star alleges Safeco built its products and services on "network architectures having features which utilized the patented invention of at least claim 16," and that the patent has had significant commercial value for the defendants.
Venue is a notable piece of the story. Lone Star says Safeco "maintains an established place of business in the state of Texas including in this district at 7900 Windrose Avenue, Plano, Texas, 75024" - the address used to anchor jurisdiction in the Eastern District of Texas.
Lone Star is seeking a judgment of infringement, damages "adequate to compensate Lone Star for Safeco's infringement" along with interest, costs and an accounting, and a declaration that the case is exceptional under 35 U.S.C. § 285, which would open the door to attorneys' fees. The plaintiff has demanded a jury trial. The complaint does not name a damages figure.
For insurers, the case is a reminder that document handling systems can attract patent claims years after deployment, and that a notice letter sent years earlier can become part of the record once a complaint is filed.
The allegations have not been tested in court. The defendants have not yet filed a response, and no court has ruled on the merits.
