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Asset Manager ← All Institutions

Flagship Pioneering, LLC

Q4 2025 · Filed 2026-02-17

Q1 2026 Q4 2025 Q3 2025 Q2 2025

Market Value

$324M

+10.7%

Holdings

New Purchases

Added To

Closed

Reduced

Top 10 Concentration

100.0%

Turnover

0.0%

Top Buys (by % of Portfolio)

Symbol	Cur %	Prior %	Chg %	Value
MRNA	42.16%	40.89%	+1.27%	$137M
SANA	31.40%	30.33%	+1.07%	$102M

Top Sells (by % of Portfolio)

Symbol	Cur %	Prior %	Chg %	Value
MCRB	5.32%	7.60%	-2.28%	$17M
FHTX	21.12%	21.18%	-0.06%	$68M

Sector Allocation Over Time

Market Cap Concentration

Tier	Holdings	Value	Weight
Large Cap	1	$137M	42.2%
Small Cap	1	$102M	31.4%
Micro Cap	2	$86M	26.4%

Portfolio Analytics

Avg Market Cap

$4.9B

Median Market Cap

$551M

Avg P/E

—

Median P/E

—

Avg Dividend Yield

—%

Avg Beta

1.58

# Stocks

# ETFs / Funds

Top Holdings (4 total)

#	Symbol	% Port	Shares	Value	Avg Price	Q/Q Value Chg	Share Chg	Chg %
1	MRNA	42.16%	4,632,149	$137M	$29.49	$17M	—	—
2	SANA	31.40%	25,001,856	$102M	$4.07	$13M	—	—
3	FHTX	21.12%	12,674,120	$68M	$5.40	$6M	—	—
4	MCRB	5.32%	1,155,850	$17M	$14.91	-$5M	—	—

View SEC EDGAR Filings for Flagship Pioneering, LLC →