Alnylam Pharmaceuticals

ALNY · NASDAQ

$230.71−$2.58 (−1.11%)TodayMarket closed ·
Prev close $233.29

Who owns ALNY

Largest institutional holders, from their latest 13F filings

The 10 largest institutions hold 52.4% of ALNY’s shares.

  • Fidelity Management & Research Company LLC10.1%
  • Capital World Investors8.3%
  • Capital Research Global Investors7.3%
  • BlackRock Institutional Trust Company, N.A.5.7%
  • Next 6 largest institutions21.0%
  • All other shareholders47.6%
Top institutional holders of ALNY
HolderShares% of shares
Fidelity Management & Research Company LLC13.46M10.08%
Capital World Investors11.14M8.35%
Capital Research Global Investors9.75M7.30%
BlackRock Institutional Trust Company, N.A.7.60M5.69%
Vanguard Portfolio Management, LLC6.54M4.90%
Vanguard Capital Management, LLC6.03M4.52%
T. Rowe Price Investment Management, Inc.5.64M4.23%
Invesco Capital Management LLC3.65M2.73%
State Street Investment Management (US)3.56M2.66%
Geode Capital Management, L.L.C.2.64M1.97%

Largest mutual fund holders

Top mutual fund holders of ALNY
HolderShares% of shares
American Funds Growth Fund of America7.62M5.71%
Vanguard Total Stock Market Index Fund4.25M3.18%
American Funds AMCAP Fund4.10M3.07%
Vanguard Mid-Cap Index Fund2.89M2.16%
Invesco QQQ Trust2.87M2.15%

Insider trades

Form 4 filings by officers, directors and large holders

Over the last 6 months, insiders sold $1.54M (6 trades) of ALNY on the open market, with no buys.

Latest ALNY insider transactions
InsiderTypeSharesValue
SUPRAN BRYANSale1.76K$398.86K
Greenstreet YvonneAward107—
Cravatt BenjaminAward4.39K—
PYOTT DAVID E IOption exercise3.83K—
PYOTT DAVID E ISale17$5.15K
PYOTT DAVID E ISale495$148.86K
PYOTT DAVID E ISale1.22K$366.44K
PYOTT DAVID E ISale1.18K$351.22K
PYOTT DAVID E ISale921$274.19K
PYOTT DAVID E IOption exercise3.83K—

Congressional trades

Disclosed by members of Congress over the last 12 months

ALNY trades disclosed by members of Congress
MemberTypeAmountTraded
Cory A BookerSenatorSale (Full)$1K–$15KAug 11, 2026

Short interest

Settled Sep 30, 2026

Shares short
7.71M
Days to cover
6.45
% of shares outstanding
5.78%
Average daily volume
1.20M
Change since last report
+7.2%

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