Tempus to buy Personalis for $1.5 billion in cancer test deal

Tempus agreed to buy Personalis in an all-stock deal valued at $1.5 billion, giving the Chicago company a bigger stake in molecular residual disease testing and genomic cancer surveillance. Personalis shareholders are set to receive $16.25 a share, a 5.6% premium to the prior close, as Tempus folds the Fremont, California, company into its precision-medicine platform.

The market response was swift. Personalis shares fell 5% in premarket trading and Tempus slipped 4% after the announcement, a reminder that investors see the transaction as strategically important but expensive. Tempus said the combination brings together Personalis’ MRD technology with its commercial scale, multimodal data and AI platform, a mix aimed at hospitals, physicians, pharmaceutical companies and researchers that need more precise tools for cancer decisions.

The acquisition lands as Tempus is already showing real scale in oncology diagnostics. In its first quarter of 2026, the company reported revenue of $348.1 million, up 36.1% from a year earlier, while Diagnostics revenue reached $261.1 million, up 34.7%. Tempus also said MRD volume was about 6,500 tests in the quarter, roughly 500% higher than a year earlier, signaling that the market for blood-based cancer monitoring is moving from promise to revenue.

Personalis has been pushing in the same direction. On Feb. 10, 2026, the company said Medicare would cover its NeXT Personal MRD test for surveillance of stage I to III non-small cell lung cancer, following earlier coverage in breast cancer. The company has also highlighted NeXT Personal data from ASCO 2026 and other studies, including claims of early colorectal cancer recurrence detection and ultrasensitive MRD performance across tumor types. That kind of coverage and clinical evidence matters because MRD testing can help doctors detect residual disease earlier than imaging in some cases and potentially match patients to treatment sooner.

For cancer care, the deal reflects how diagnostics and genomic data have become strategic assets rather than side businesses. Hospitals are under pressure to choose tools that can support tumor profiling, companion diagnostics and patient stratification, while drugmakers want real-world evidence that can speed development and sharpen trial design. If Tempus integrates Personalis successfully, it could widen the competition among precision-oncology platforms that are trying to turn lab results, software and machine learning into a single clinical and commercial workflow.