Byers Capital

Brook Byers serves as the managing partner, with his son Sean Byers playing an active co-investing role. Brook Byers built his career as a general partner at Kleiner Perkins Caufield & Byers, where he focused on life sciences for over 40 years. Sean Byers sources and underwrites technology and consumer-facing health investments, reflecting a deliberate transfer of generational investment authority.

The family's wealth originates from Brook Byers's career at Kleiner Perkins, which he joined in 1977. Over four decades, he was instrumental in founding and funding over 60 life science companies that achieved public listings or acquisitions, spanning from Genentech in the early 1980s to genomic medicine companies in the 2010s. Carried interest and direct equity from those outcomes form the asset base.

Sourcing relies on Brook Byers's network built over 45 years in venture capital, which includes deep ties to Stanford University, UCSF, and academic research commercialization offices in the Bay Area. The office often enters deals shared by peer venture firms — particularly life science specialists — and leans heavily on the founder relationships and scientific advisory board connections Byers developed at Kleiner Perkins.

Yes, Brook Byers has historically taken board positions in select portfolio companies, a practice he carried over from his Kleiner Perkins tenure. In the family office context, board service is likely selective and reserved for companies where the exposure is large or the scientific domain aligns closely with his expertise, though specific current board roles are not systematically disclosed.

Byers Capital functions as a single family office managing the capital of the Brook Byers family. It does not register as an investment advisor or openly solicit third-party capital. The office's deployment pattern — unconstrained, stage-agnostic, and focused on fields where the family holds a knowledge edge — conforms to the structure of a pure family vehicle.

The office invests from seed to growth equity, often as a first-institutional-check alongside syndicated venture rounds. Byers Capital has entered companies at the Series A stage in synthetic biology and CRISPR platforms and has participated in later rounds for digital health companies like K Health. AUM is not disclosed, which is characteristic of a family office that can size checks opportunistically against its balance sheet rather than against fund-level constraints.

Byers Capital has no formal affiliation with Kleiner Perkins Caufield & Byers. The link is biographical: Brook Byers spent his career as a GP at Kleiner Perkins, and the family office invests proceeds earned during that tenure. The two entities may occasionally co-invest, but there is no structural or economic relationship.