Tempus AI agreed to acquire Personalis in a $1.5 billion deal, adding a molecular residual disease offering built on tumor-informed sequencing to Tempus’ cancer diagnostics portfolio. Tempus said the acquisition will help it support patients around diagnostics, treatment selection, recurrence monitoring, and broader clinical decision-making. The planned purchase includes a $16.25 per-share offer and could split payment between cash and other consideration, with a close expected in late 2026 or early 2027 subject to approvals. Personalis’ tumor-informed MRD test uses information from a patient’s tumor sample, while Tempus’ existing MRD tools are tumor-naive. The companies pointed to accelerating market interest in MRD assays and noted expanding insurance coverage, including Medicare in multiple indications. For biotech and medtech investors, the transaction reinforces how quickly diagnostics platforms are consolidating to capture repeatable revenue from monitoring workflows.