A federal judge has ordered Guardant Health to pay more than $245.2 million to TwinStrand Biosciences and the University of Washington in a patent dispute involving DNA-sequencing technology used in cancer testing.
The final judgment preserves a 2023 jury verdict finding that Guardant willfully infringed two patents underlying TwinStrand’s Duplex Sequencing technology. According to TwinStrand, the case did not allege that Guardant stole its complete test or confidential files. Instead, the jury found that Guardant used methods covered by the patents in 11 of its own cancer-testing products without obtaining a license.
In addition to damages, accrued royalties, and interest, the US District Court for the District of Delaware ordered Guardant to pay a 6% royalty on US sales of 11 covered products and services through March 15, 2033, when the patents expire.
The affected products include the Guardant360 laboratory-developed test, Guardant360 CDx, Guardant Reveal, Guardant360 Response, Guardant HEME, and Guardant Shield, along with several other precision oncology products and services. Guardant also must provide TwinStrand and the university with quarterly reports of US sales.
Guardant reported 2025 annual revenue of $982 million, an increase of 33% from 2024. The company sold more than 360,000 tests in 2025. It noted in more recent earnings highlights that a version of Gaurdant Shield had been added to the American Cancer Society’s updated colorectal cancer screening guidelines.
For clinical laboratory and pathology leaders, the ruling illustrates how ownership of sequencing methods can influence the economics of commercial cancer testing. Continuing royalty obligations could increase the cost of offering affected assays to lab customers, although Guardant has not indicated that it will raise test prices or change laboratory access.
Patents cover technology designed to improve accuracy
TwinStrand stated that its technology independently sequences and compares both strands of a DNA molecule. The approach is intended to help distinguish rare genetic variants from background sequencing errors—an important capability in liquid biopsy, molecular residual disease testing, and other cancer applications involving low levels of tumor DNA.
“Duplex sequencing solved an accuracy problem the sequencing field had worked on for years, and this judgment affirms the jury’s finding that Guardant Health built products on that invention without a license,” said Chad Waite, chair of the TwinStrand board of directors. “We remained steadfast in our conviction that the facts would prevail, and they have. We intend to see this through and stand firmly behind the intellectual property at the core of our technology.”
Guardant plans to appeal. The company said the judgment concerns products that existed at the time of the 2023 trial and that many have since been discontinued or substantially modified. Guardant also maintains that current versions of its Reveal and Shield tests are not covered by the district court’s order, GeekWire reported.
The judgment and potential royalty collections will be stayed while the appeal proceeds. Nevertheless, a fair long-term concern is how Gaurdant might absorb a judgment that represents more than 25% of its annual revenue .
This article was created with the assistance of Generative AI and has undergone editorial review before publishing.
