Two legal and regulatory developments touched Guardant Health this week. The US Court of Appeals remanded a patent‑infringement dispute between Guardant, TwinStrand Biosciences and the University of Washington back to the Patent Trial and Appeal Board for further review, potentially improving Guardant’s path to reduce or eliminate earlier jury damages. The case concerns duplex consensus sequencing patents and prior jury awards and royalty calculations. Separately the FDA approved Guardant360 CDx as a companion diagnostic for Pfizer’s encorafenib plus cetuximab and chemotherapy regimen in BRAF V600E–mutant metastatic colorectal cancer, expanding the liquid biopsy’s list of companion indications. Guardant framed the approval as validation of ctDNA assays for treatment selection and monitoring. Why it matters: the court remand could materially affect Guardant’s patent exposure and potential damages, while the FDA approval expands the clinical and commercial utility of liquid biopsy as a non‑invasive companion diagnostic (CDx).