A U.S. District Court ordered Guardant Health to pay TwinStrand Biosciences and the University of Washington more than $245 million over patent infringement tied to duplex sequencing methods. The ruling includes damages, royalties and interest, following a prior 2023 decision that already found liability. The order calls for an ongoing 6% royalty rate on multiple products and services using duplex consensus sequencing approaches, and it requires quarterly accounting of U.S. sales of the covered offerings. The patents involve methods to reduce error rates in massively parallel DNA sequencing. Guardant has indicated it is preparing for an appeal while it continues challenges at the PTAB level, but the damages and royalty obligation create immediate financial and strategic pressure on sequencing-based liquid biopsy workflows.