Stocks/Funds/CIK 1400240

Flagship Pioneering Inc.

long-term holderconcentrated
Quarterly 13F filings · Latest period 2026-03-31 · CIK 1400240
Assets
$1.16B
+392.7% YoY
Holdings
5
Lifetime alpha vs market
-42.99% annual
Average hold time
3.9 yr
median 5.3 yr

Quarterly history

Cum return -84% vs S&P +52% · α -136% lifetimeAUM $1.2B · peak $9.5BFlow $783M (+242%)2016-092018-032019-092021-032022-092024-032025-092026-03
AUM ($B)fundS&P 500(gap = α)/ Flow in/out

Behavior signals (lifetime)

Dip response
-1.83%
trims when stocks drop
when a holding falls −10%+
Middle response
-0.30%
baseline attrition
Rally response
-5.33%
trims into rallies
when a holding rises +10%+

Top positions · 5

Ticker$ value% portYoYHold time
GENBGenerate Biomedicines, I$783M67.4%0.3 yr
MRNAModerna, Inc.$235M20.3%+79.2%7.5 yr
SANASana Biotechnology, Inc.$72M6.2%+71.4%5.3 yr
FHTXFoghorn Therapeutics Inc$61M5.2%+31.0%5.5 yr
MCRBSeres Therapeutics, Inc.$10M0.9%-36.6%1.0 yr

Portfolio composition (YoY)

Industry mix
Asset Management67.4%$783M
Biotechnology32.6%-60.6pp$378M
Country
US100.0%+6.9pp
Top 5: 100.0% · Top 10: 100.0% · Top 25: 100.0%

Winners

TickerPrev $PnLYoY %
MRNA$131M+0.10B79.2%
SANA$42M+0.03B71.4%
FHTX$46M+0.01B31.0%

Losers

TickerPrev $PnLYoY %

Top buys this quarter · 1

GENB Generate Biomedicines, Inc.new+$783M

Top sells this quarter · 0

No sells this quarter

Quarterly history (TTM returns)

PeriodAUM# PosReturn (1yr)SPY (1yr)Alpha (1yr)Flow
2026-03-31$1.16B5+62.12%+17.59%+44.53%+0.78B
2025-12-31$324M4+4.04%+17.72%-13.68%+0.00B
2025-09-30$293M4-48.18%+17.52%-65.70%+0.00B
2025-06-30$268M4-66.72%+14.94%-81.66%-0.00B
2025-03-31$236M4-71.21%+8.30%-79.51%-0.01B
2024-12-31$334M5-54.55%+24.89%-79.44%+0.01B
2024-09-30$592M6-18.37%+36.04%-54.41%+0.00B
2024-06-30$843M6-4.72%+24.49%-29.21%-0.67B
2024-03-31$1.52B7-16.33%+29.62%-45.95%-0.04B
2023-12-31$1.33B7-59.61%+26.18%-85.79%-0.04B
2023-09-30$1.38B9-57.19%+21.57%-78.76%-0.45B
2023-06-30$2.24B10-52.50%+19.42%-71.92%-0.01B
2023-03-31$2.57B11-58.84%-7.82%-51.02%+0.79B
2022-12-31$3.13B12+5.00%+7.56%-2.57%+0.64B
2022-09-30$2.38B12-9.33%-4.93%-4.40%-0.03B
2022-06-30$2.65B12-24.24%-16.11%-8.13%-0.57B