Alnylam Pharmaceuticals, Inc. (ALNY) Institutional Ownership

Institutions by Trading Activity

Ownership Statistics

0Shares Outstanding

4,706,447Shares held by institutions

$1,487,754,961Value of institutional holdings

101.86%Institutional ownership %

2.14%Shares Changed QoQ

646No. of institutional investors

Shares Owned by Institutions

Shares Purchased/Sold by Institutions

Ownership Summary

Alnylam Pharmaceuticals, Inc. (NASDAQ:ALNY) has 823 institutional investors with active 13F positions as of December 2025.

These investors held 94.8% of outstanding shares in December 2025, down from 102.0% in September 2025.
Their total shares held in ALNY decreased -4.23% quarter over quarter, and separately, investors owning Alnylam Pharmaceuticals increased 40.92% from a year ago.
Of these 823 funds, 442 grew their exposure to Alnylam Pharmaceuticals, 283 cut back, and 98 maintained positions.
In total, institutional investors held 129.18Mn shares in Alnylam Pharmaceuticals as of December 2025, down by 5.7Mn shares quarter on quarter, and down 2.5Mn shares year over year.
As of December 31, 2025, the biggest holder of Alnylam Pharmaceuticals is Capital World Investors at 16.3Mn shares, representing 11.96% of shares outstanding.
The most significant purchases of ALNY for the quarter ending December 2025 came from NORGES BANK (2.25Mn), T. Rowe Price Investment Management, Inc. (731.0K), Invesco Ltd. (684.0K), BlackRock, Inc. (497.27K), Rockefeller Capital Management L.P. (355.97K).
Top sellers of ALNY stock for the quarter ending December 2025 included Jpmorgan Chase & Co (4.37Mn), GROUPAMA ASSET MANAGMENT (4.0Mn), Bank Of America Corp /De/ (2.31Mn), FMR LLC (865.48K), JANE STREET GROUP, LLC (647.46K).
Per Business Quant, the top 10 investors in ALNY for the quarter ending December 2025 include Capital World Investors (16.3Mn), FMR LLC (15.9Mn), VANGUARD GROUP INC (13.55Mn), BlackRock, Inc. (10.4Mn), Capital Research Global Investors (6.78Mn), Jpmorgan Chase & Co (4.72Mn), State Street Corp (3.23Mn), T. Rowe Price Investment Management, Inc. (2.9Mn), GEODE CAPITAL MANAGEMENT, LLC (2.65Mn), BAILLIE GIFFORD & CO (2.6Mn).

825 Institutional Holders

4,706,447 Total Shares Held

Rows:

Download Data

Owner Name	Date	Change (QoQ)	Change (%)	Value (USD)
BlackRock, Inc.	31 Dec, 2025	497,273	5.02%	$0.00
Capital World Investors	31 Dec, 2025	-132,481	-0.81%	$0.00
T. Rowe Price Investment Management, Inc.	31 Dec, 2025	731,003	33.63%	$0.00
Rockefeller Capital Management L.P.	31 Dec, 2025	364,093	8,312.63%	$0.00
FMR LLC	31 Dec, 2025	-865,476	-5.16%	$0.00
Orbis Allan Gray Ltd	31 Dec, 2025	-332,743	-17.06%	$0.00
Barclays Plc	31 Dec, 2025	22,968	11.51%	$0.00
VANGUARD GROUP INC	31 Dec, 2025	-11,520	-0.08%	$0.00
UBS Group AG	31 Dec, 2025	337,640	69.16%	$0.00
HSBC HOLDINGS PLC	31 Dec, 2025	106,020	145.21%	$0.00
Capital Research Global Investors	31 Dec, 2025	-443,132	-6.14%	$0.00
Qube Research & Technologies Ltd	31 Dec, 2025	-36,602	-4.51%	$0.00
Osbon Capital Management LLC	31 Dec, 2025	18	0.00%	$0.00
Jpmorgan Chase & Co	31 Dec, 2025	-4,367,541	-48.06%	$0.00
Nuveen, LLC	31 Dec, 2025	-22,032	-3.75%	$0.00
Purpose Unlimited Inc.	31 Dec, 2025	4	0.00%	$0.00
PEAK6 LLC	31 Dec, 2025	1	33.33%	$0.00
State Street Corp	31 Dec, 2025	147,481	4.79%	$0.00
Bellevue Group AG	31 Dec, 2025	-621	-0.14%	$0.00
GEODE CAPITAL MANAGEMENT, LLC	31 Dec, 2025	151,480	6.06%	$0.00

1 - 20 of 825

Research Tools