Alnylam Pharmaceuticals Inc (ALNY) Ownership

458.12 ↓7.22 (-1.55%)

As of December 31, 1969, 7:00pm EST.

Institutions
Mutual Funds

Institutional Ownership

Capital World Investors is the biggest individual institutional holder of Alnylam Pharmaceuticals Inc (ALNY), owning a total of 16.8 million shares. Combined, the top 39 institutional holders of ALNY own 105.49% of the company with a total of 136.8 million shares.

In the latest ownership report on June 30th 2025, the top 39 institutional holders decreased their combined ownership of ALNY by 896 thousand shares. 6 institutions bought 1,349,407 total additional shares and increased their ownership by an average of 6.26%. However 7 institutions sold 2,245,785 total shares and decreased their ownership by an average of 10.52%.

Overall this is a negative sign as the number of shares owned by the top 20 institutional holders of Alnylam Pharmaceuticals decreased by a net total of -896,378 in the latest quarter.

Institution Ownership Chart

Latest Institutional Ownership Changes

Owner	Percent Owned	Percent Change	Shares Owned	Share Change	Date Reported
Capital World Investors	12.821%	0.331%	16,805,007	55,384	2025-06-30
FMR Inc	12.059%	3.244%	15,806,521	496,661	2025-06-30
Vanguard Group Inc	10.144%	1.842%	13,297,139	240,534	2025-06-30
Capital Research Global Investors	5.487%	0.516%	7,191,656	36,928	2025-06-30
Regeneron Pharmaceuticals Inc	3.391%	0.000%	4,444,445	0	2025-06-30
T. Rowe Price Investment Management,Inc.	3.266%	-3.098%	4,281,279	-136,866	2025-06-30
Dodge & Cox	2.439%	-4.615%	3,197,096	-154,666	2025-06-30
T. Rowe Price Associates, Inc.	2.399%	-10.275%	3,145,006	-360,162	2025-06-30
Baillie Gifford & Co Limited.	2.313%	-17.107%	3,031,891	-625,716	2025-06-30
Orbis Allan Gray Ltd	1.618%	29.756%	2,121,412	486,489	2025-06-30
Wellington Management Company LLP	1.584%	-20.499%	2,075,752	-535,234	2025-06-30
NORGES BANK	1.551%	-17.239%	2,032,680	-423,402	2025-06-30
American Century Companies Inc	1.369%	1.898%	1,793,846	33,411	2025-06-30
Winslow Capital Management, LLC	0.898%	-0.820%	1,177,439	-9,739	2025-06-30

Top Institutions

Owner	Percent Owned	Percent Change	Shares Owned	Share Change	Date Reported
Capital World Investors	12.821%	0.331%	16,805,007	55,384	2025-06-30
Nuveen Asset Management, LLC	13.368%	5,486.110%	16,593,268	16,296,223	2022-09-30
FMR Inc	12.059%	3.244%	15,806,521	496,661	2025-06-30
Vanguard Group Inc	10.144%	1.842%	13,297,139	240,534	2025-06-30
BlackRock Inc	7.293%	-3.297%	9,559,382	-325,875	2025-03-31
Capital Research Global Investors	5.487%	0.516%	7,191,656	36,928	2025-06-30
Regeneron Pharmaceuticals Inc	3.391%	0.000%	4,444,445	0	2025-06-30
T. Rowe Price Investment Management,Inc.	3.266%	-3.098%	4,281,279	-136,866	2025-06-30
State Street Corp	2.568%	-1.645%	3,366,583	-56,294	2025-03-31
Dodge & Cox	2.439%	-4.615%	3,197,096	-154,666	2025-06-30
State Street Corporation	2.486%	2.335%	3,191,373	72,821	2024-03-31
T. Rowe Price Associates, Inc.	2.399%	-10.275%	3,145,006	-360,162	2025-06-30
Baillie Gifford & Co Limited.	2.313%	-17.107%	3,031,891	-625,716	2025-06-30
Geode Capital Management, LLC	1.772%	5.258%	2,322,834	116,034	2025-03-31
JPMorgan Chase & Co	1.693%	-1.386%	2,218,872	-31,188	2025-03-31
Orbis Allan Gray Ltd	1.618%	29.756%	2,121,412	486,489	2025-06-30
Wellington Management Company LLP	1.584%	-20.499%	2,075,752	-535,234	2025-06-30
NORGES BANK	1.551%	-17.239%	2,032,680	-423,402	2025-06-30
American Century Companies Inc	1.369%	1.898%	1,793,846	33,411	2025-06-30
RTW INVESTMENTS, LLC	1.297%	-2.543%	1,640,559	-42,803	2023-12-31
Groupama Asset Management	1.175%	0.765%	1,540,139	11,689	2025-03-31
Morgan Stanley - Brokerage Accounts	1.150%	9.808%	1,483,028	132,466	2024-06-30
Capital Research & Mgmt Co - Division 3	1.088%	-64.275%	1,418,602	-2,552,261	2024-12-31
Amundi	0.963%	31.921%	1,195,909	289,375	2022-09-30
Winslow Capital Management, LLC	0.898%	-0.820%	1,177,439	-9,739	2025-06-30
venBio Select Advisor LLC	0.878%	9.890%	1,111,111	100,000	2023-12-31
Bank of America Corp	0.812%	154.347%	1,064,573	646,021	2025-03-31
Amvescap Plc.	0.697%	63.618%	913,792	355,302	2025-03-31
Legal & General Group PLC	0.676%	6.297%	881,111	52,194	2025-03-31
Manufacturers Life Insurance Co	0.682%	-49.330%	839,015	-816,820	2022-09-30
Bank of New York Mellon Corp	0.662%	0.006%	837,131	47	2023-12-31
UBS Asset Mgmt Americas Inc	0.648%	10.118%	835,413	76,763	2024-06-30
Deep Track Capital, LP	0.648%	0.000%	832,310	832,310	2024-03-31
Bellevue Group AG	0.627%	-12.039%	809,095	-110,739	2024-09-30
Northern Trust Corp	0.608%	5.578%	780,835	41,251	2024-06-30
Massachusetts Financial Services Company	0.615%	1.354%	765,772	10,230	2023-03-31
Pictet Asset Manangement SA	0.588%	-21.110%	758,528	-202,976	2024-06-30
Loomis, Sayles & Company LP	0.608%	-9.701%	747,750	-80,329	2022-09-30
AllianceBernstein L.P.	0.549%	1,093.920%	675,007	618,470	2022-06-30

Mutual Fund Ownership

American Funds Growth Fund of Amer A is the biggest individual fund holder of Alnylam Pharmaceuticals Inc (ALNY), owning a total of 10.2 million shares. Combined, the top 33 mutual fund holders of ALNY own 66.88% of the company with a total of 86.8 million shares.

In the latest ownership report on July 31st 2025, the top 33 fund holders increased their combined ownership of ALNY by 134 thousand shares. 2 funds bought 37,186 total additional shares and increased their ownership by an average of 0.74%. However 2 funds sold 171,293 total shares and decreased their ownership by an average of 3.08%.

Overall this is a negative sign as the number of shares owned by the top 20 mutual funds holding Alnylam Pharmaceuticals decreased by a net total of -134,107 in the latest report.

Mutual Funds Chart

Latest Mutual Fund Ownership Changes

Owner	Percent Owned	Percent Change	Shares Owned	Share Change	Date Reported
Vanguard Total Stock Mkt Idx Inv	3.130%	-2.274%	4,102,677	-95,465	2025-07-31
Vanguard Mid Cap Index Institutional	2.219%	1.089%	2,908,500	31,326	2025-07-31
Fidelity Growth Compy Commingled Pl S	1.430%	-3.889%	1,873,824	-75,828	2025-07-31
Vanguard Growth Index Investor	1.140%	0.394%	1,494,074	5,860	2025-07-31

Top Mutual Funds

Owner	Percent Owned	Percent Change	Shares Owned	Share Change	Date Reported
American Funds Growth Fund of Amer A	7.767%	0.000%	10,181,075	0	2025-06-30
Capital Group Growth Fnd of Amer Comp	7.767%	0.000%	10,181,075	0	2025-06-30
Vanguard Total Stock Mkt Idx Inv	3.130%	-2.274%	4,102,677	-95,465	2025-07-31
Vanguard US Total Market Shares ETF	3.146%	1.351%	4,071,215	54,277	2024-09-30
Vanguard Instl Ttl Stck Mkt Idx Tr	3.065%	2.745%	3,846,587	102,757	2023-03-31
VA CollegeAmerica Amcap 529A	2.893%	21.436%	3,731,045	658,615	2024-12-31
American Funds New Perspective A	2.233%	0.000%	2,927,428	0	2025-06-30
Capital Group New Perspective Comp	2.233%	0.000%	2,927,428	0	2025-06-30
Vanguard Mid Cap Index Institutional	2.219%	1.089%	2,908,500	31,326	2025-07-31
Fidelity Growth Compy Commingled Pl 3	2.197%	0.000%	2,746,210	0	2023-07-31
Capital Group AMCAP Composite	1.832%	0.000%	2,401,920	0	2025-06-30
American Funds AMCAP A	1.832%	0.000%	2,401,920	0	2025-06-30
Dodge & Cox Stock I	1.555%	-5.996%	2,038,100	-130,000	2025-06-30
Vanguard Institutional Extnd Mkt Idx Tr	1.533%	-0.463%	2,009,838	-9,345	2025-06-30
Fidelity Growth Compy Commingled Pl O	1.490%	0.000%	1,912,383	0	2024-08-31
Fidelity Growth Compy Commingled Pl S	1.430%	-3.889%	1,873,824	-75,828	2025-07-31
Vanguard Extended Market Index Investor	1.389%	0.312%	1,736,048	5,407	2023-08-31
American Funds IS® Growth 1	1.286%	0.000%	1,686,200	0	2025-06-30
Capital Group Growth Composite	1.286%	0.000%	1,686,200	0	2025-06-30
Fidelity® Growth Company	1.307%	-6.577%	1,640,658	-115,500	2023-11-30
American Funds Fundamental Invs A	1.224%	0.000%	1,604,154	0	2025-06-30
Capital Group Fundamental Invtrs Comp	1.224%	0.000%	1,604,154	0	2025-06-30
Vanguard Health Care Inv	1.223%	-23.899%	1,603,352	-503,516	2025-06-30
T. Rowe Price US Mid-Cap Growth Equity	1.220%	-2.702%	1,598,800	-44,400	2025-06-30
T. Rowe Price Mid-Cap Growth	1.220%	-0.075%	1,598,800	-1,200	2025-06-30
American Funds New Economy A	1.169%	-4.668%	1,532,833	-75,047	2025-06-30
Capital Group New Economy Comp	1.169%	-4.668%	1,532,833	-75,047	2025-06-30
T. Rowe Price New Horizons	1.220%	3.370%	1,519,629	49,538	2023-03-31
Fidelity OTC	1.146%	-1.602%	1,501,624	-24,445	2025-06-30
US Small-Cap Growth II Equity Comp	1.193%	0.000%	1,496,556	1,496,556	2023-06-30
Vanguard Growth Index Investor	1.140%	0.394%	1,494,074	5,860	2025-07-31
Fidelity Growth Company Fund	1.070%	-0.340%	1,373,787	-4,686	2024-06-30
T. Rowe Price Health Sciences	1.074%	15.580%	1,358,790	183,164	2024-03-31