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Asset Manager ← All Institutions

Flagship Pioneering, LLC

Q2 2025 · Filed 2025-08-14

Q1 2026 Q4 2025 Q3 2025 Q2 2025

Market Value

$268M

+22.3%

Holdings

New Purchases

Added To

Closed

Reduced

Top 10 Concentration

100.0%

Turnover

25.0%

Top Buys (by % of Portfolio)

Symbol	Cur %	Prior %	Chg %	Value
SANA	25.42%	19.13%	+6.30%	$68M
MCRB	4.78%	0.00%	+4.78%	$13M
FHTX	22.19%	21.07%	+1.12%	$60M

Top Sells (by % of Portfolio)

Symbol	Cur %	Prior %	Chg %	Value
MRNA	47.60%	59.80%	-12.20%	$128M

Sector Allocation Over Time

Market Cap Concentration

Tier	Holdings	Value	Weight
Large Cap	1	$128M	47.6%
Small Cap	1	$68M	25.4%
Micro Cap	2	$72M	27.0%

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 %	Status
1	MRNA	47.60%	4,632,149	$128M	$27.59	-$4M	—	—
2	SANA	25.42%	25,001,856	$68M	$2.73	$26M	—	—
3	FHTX	22.19%	12,674,120	$60M	$4.70	$13M	—	—
4	MCRB	4.78%	1,155,850	$13M	$11.11	—	+1,155,850	—	NEW

New Positions

Symbol	Value	% Port
MCRB	$13M	4.78%

View SEC EDGAR Filings for Flagship Pioneering, LLC →