Logos Capital is a San Francisco-based fundamental biotechnology-focused investment firm founded in 2019 by Dr. Arsani William, a Harvard MD and Stanford MBA with prior experience at Farallon Capital Management. The firm combines scientific and financial expertise with a proprietary Logos Analytics platform that models clinical trial outcomes to achieve high conviction in each position.

Logos Capital invests in private and public biotechnology companies, typically at Series B, C, and D stages. It participated as an existing investor in Beacon Biosignals' $86M Series B round in November 2025, along with Casdin Capital and General Catalyst. Its broader portfolio spans 151+ investments across biotech and life sciences.

Logos Capital is headquartered in San Francisco and invests primarily in the United States with broad international biotech exposure. For neurotech, it is most relevant for clinical-stage brain health and neuroscience companies with strong data packages and clear therapeutic pathways.