Foresite Capital Management IV, LLC Quarterly 13F Portfolio Update (Q2 2026)

Foresite Capital Management IV, LLC's disclosed holdings carry a Herfindahl concentration index of 0.384 — mathematically equivalent to about 3 equally-sized positions, well below its 6 actual disclosed holdings. That gap points to a strategy built around a small core of high-conviction bets rather than broad diversification.

Position sizes vary widely across the portfolio (a coefficient of variation of 1.25), with a handful of outsized bets alongside many smaller positions.

Recent activity leans toward adding more aggressively to already-large existing positions than to newly initiated ones (a 7.2 percentage-point tilt) — a pattern consistent with a momentum-following approach.

Sector classification currently covers about 21% of this portfolio's disclosed value; the remainder includes holdings (e.g. unmapped tickers, options, or other security types) not yet covered by our sector mapping.