Flagship Pioneering, LLC 13F Holdings Overview (7 Positions)

Flagship Pioneering, LLC's disclosed holdings carry a Herfindahl concentration index of 0.503 — mathematically equivalent to about 2 equally-sized positions, well below its 7 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 1.38), with a handful of outsized bets alongside many smaller positions.

Recent activity leans toward initiating meaningfully larger new positions than it adds to existing ones (a 67.4 percentage-point tilt) — a pattern consistent with a more contrarian, new-idea-driven approach.

Sector classification currently covers about 20% 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.