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Asset Manager ← All Institutions

Flagship Pioneering, LLC

Q3 2025 · Filed 2025-11-14

Q1 2026 Q4 2025 Q3 2025 Q2 2025

Market Value

$293M

+9.0%

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
SANA	30.33%	25.42%	+4.91%	$89M
MCRB	7.60%	4.78%	+2.82%	$22M

Top Sells (by % of Portfolio)

Symbol	Cur %	Prior %	Chg %	Value
MRNA	40.89%	47.60%	-6.72%	$120M
FHTX	21.18%	22.19%	-1.01%	$62M

Sector Allocation Over Time

Market Cap Concentration

Tier	Holdings	Value	Weight
Large Cap	1	$120M	40.9%
Small Cap	1	$89M	30.3%
Micro Cap	2	$84M	28.8%

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	40.89%	4,632,149	$120M	$25.83	-$8M	—	—
2	SANA	30.33%	25,001,856	$89M	$3.55	$21M	—	—
3	FHTX	21.18%	12,674,120	$62M	$4.89	$2M	—	—
4	MCRB	7.60%	1,155,850	$22M	$19.24	$9M	—	—

View SEC EDGAR Filings for Flagship Pioneering, LLC →