ALNYLAM PHARMACEUTICALS, INC. - COMMON STOCK (ALNY) Institutional Ownership

13F Institutional Holders and Ownership History from Q1 2014 to Q4 2025

Type / Class
Equity / COMMON STOCK
Symbol
ALNY on Nasdaq
Shares outstanding
131,516,365
Price per share
$354.75
All holders as of 31 Dec 2025
Q4 2025
Total 13F shares
129,251,561
Total reported value
$51,412,787,304
% of total 13F portfolios
0.01%
Share change
-1,042,773
Value change
-$556,156,336
Number of holders
822
Price from insider filings
$354.75
Reported Shares, Excluding Options vs Price
Reported Value, Excluding Options
Total Investors

Significant Owners of ALNYLAM PHARMACEUTICALS, INC. - COMMON STOCK (ALNY) based on Schedule 13D/G filings

Filer Ownership Change % Holdings Value Net Change Nb Shares Change % Reporting Name Report Period
FMR LLC 13% $7,676,347,201 16,834,095 FMR LLC 30 Sep 2025
VANGUARD GROUP INC 10% $3,167,662,939 13,056,605 The Vanguard Group 31 Mar 2025
Capital Research Global Investors 5.4% $1,690,630,939 6,968,513 Capital Research Global Investors 31 Dec 2024

As of 31 Dec 2025, 822 institutional investors reported holding 129,251,561 shares of ALNYLAM PHARMACEUTICALS, INC. - COMMON STOCK (ALNY). This represents 98% of the company’s total 131,516,365 outstanding shares.

Top 25 Institutional Shareholders

The largest institutional shareholders of ALNYLAM PHARMACEUTICALS, INC. - COMMON STOCK (ALNY) together control 75% of the company’s outstanding shares — a level of ownership often associated with strong institutional conviction and long‑term capital commitment.

Institution Ownership % Shares Held Share Change % Portfolio % Holdings Value
Capital World Investors 12% 16,301,772 -0.81% 0.88% $6,482,389,029
FMR LLC 12% 15,902,149 -5.2% 0.32% $6,323,489,463
VANGUARD GROUP INC 10% 13,553,932 -0.08% 0.08% $5,389,721,059
BlackRock, Inc. 7.9% 10,400,874 +5% 0.07% $4,135,907,609
Capital Research Global Investors 5.2% 6,779,708 -6.1% 0.5% $2,695,945,984
JPMORGAN CHASE & CO 3.6% 4,719,999 +3.9% 0.13% $1,876,908,009
STATE STREET CORP 2.5% 3,228,956 +4.8% 0.04% $1,283,994,353
GEODE CAPITAL MANAGEMENT, LLC 2% 2,650,722 +6.1% 0.07% $1,056,883,596
BAILLIE GIFFORD & CO 2% 2,600,979 -6.8% 0.86% $1,034,279,300
NORGES BANK 1.7% 2,252,775 0.1% $895,815,979
Invesco Ltd. 1.6% 2,165,840 +46% 0.13% $861,246,230
Dodge & Cox 1.5% 1,964,415 -15% 0.42% $781,149,625
T. Rowe Price Investment Management, Inc. 1.3% 1,753,640 -19% 0.44% $697,335,000
PRICE T ROWE ASSOCIATES INC /MD/ 1.3% 1,702,831 -5.4% 0.07% $677,132,000
WELLINGTON MANAGEMENT GROUP LLP 1.2% 1,628,931 -11% 0.11% $647,744,413
Orbis Allan Gray Ltd 1.2% 1,618,219 -17% 2.7% $643,484,786
AMERICAN CENTURY COMPANIES INC 1.1% 1,485,161 -9.5% 0.3% $590,576,553
TWO SIGMA ADVISERS, LP 0.86% 1,132,560 +27% 0.88% $450,362,484
ARROWSTREET CAPITAL, LIMITED PARTNERSHIP 0.86% 1,127,162 -17% 0.26% $448,215,969
MORGAN STANLEY 0.74% 970,157 +34% 0.02% $385,784,277
Legal & General Group Plc 0.73% 961,496 +8.3% 0.08% $382,338,888
AQR CAPITAL MANAGEMENT LLC 0.7% 919,959 +24% 0.19% $365,821,629
NORTHERN TRUST CORP 0.65% 857,742 +3% 0.04% $341,081,107
UBS Group AG 0.63% 825,840 +69% 0.07% $328,395,275
FRANKLIN RESOURCES INC 0.6% 787,623 +10% 0.08% $313,198,267

Institutional Holders of ALNYLAM PHARMACEUTICALS, INC. - COMMON STOCK (ALNY) across Reporting Periods

Period Reported Shares, Excl. Options Value, Excl. Options Value Change Price (Median) Investors
2025 Q4 129,251,561 $51,412,787,304 -$556,156,336 $397.65 822
2025 Q3 129,763,359 $59,161,634,764 -$748,502,355 $456.00 813
2025 Q2 132,062,946 $43,060,444,035 +$1,728,282,756 $326.09 645
2025 Q1 126,881,187 $34,233,011,857 -$90,968,751 $270.02 615
2024 Q4 127,632,870 $30,037,175,866 -$216,265,374 $235.31 587
2024 Q3 123,754,217 $34,035,461,284 +$1,116,635,795 $275.03 559
2024 Q2 119,818,858 $29,121,298,158 +$1,425,600,934 $243.00 514
2024 Q1 114,506,382 $17,112,788,490 -$462,345,987 $149.45 488
2023 Q4 117,037,909 $22,406,153,370 -$144,088,009 $191.41 491
2023 Q3 117,774,911 $20,850,702,200 -$144,549,642 $177.10 445
2023 Q2 118,559,398 $22,525,153,339 -$212,624,410 $189.94 469
2023 Q1 119,657,504 $23,956,079,414 +$6,809,245 $200.32 469
2022 Q4 119,654,959 $28,425,215,078 -$3,086,850,614 $237.65 477
2022 Q3 133,393,008 $26,709,327,641 +$3,401,526,639 $200.16 479
2022 Q2 113,477,846 $16,543,858,767 -$67,066,647 $145.85 405
2022 Q1 113,908,234 $18,598,579,814 +$320,228,126 $163.29 417
2021 Q4 112,006,374 $18,989,908,067 +$63,928,357 $169.58 420
2021 Q3 111,604,687 $21,068,206,424 -$147,043,437 $188.81 395
2021 Q2 112,239,402 $19,027,485,774 +$501,915,844 $169.52 390
2021 Q1 109,361,699 $15,431,272,628 +$204,818,578 $141.19 381
2020 Q4 107,900,409 $14,018,800,907 -$114,208,967 $129.97 353
2020 Q3 108,499,178 $15,789,451,789 -$460,283,345 $145.60 347
2020 Q2 111,562,100 $16,522,566,788 +$489,977,680 $148.11 363
2020 Q1 108,370,173 $11,796,531,647 +$294,735,312 $108.85 317
2019 Q4 105,328,965 $12,129,387,603 -$233,499,979 $115.17 306
2019 Q3 108,059,417 $8,689,910,646 +$177,605,607 $80.42 276
2019 Q2 106,070,864 $7,694,654,472 +$800,559,176 $72.56 283
2019 Q1 96,763,330 $9,041,659,322 +$427,442,108 $93.45 279
2018 Q4 92,434,388 $6,736,307,943 +$108,054,744 $72.91 274
2018 Q3 90,577,162 $7,927,334,207 -$105,883,718 $87.52 297
2018 Q2 91,541,386 $9,015,538,809 -$37,011,096 $98.49 303
2018 Q1 91,623,594 $10,912,571,096 -$75,880,031 $119.10 285
2017 Q4 92,127,969 $11,704,641,437 +$613,133,919 $127.05 275
2017 Q3 87,490,797 $10,279,386,005 +$76,555,680 $117.49 228
2017 Q2 87,236,413 $6,951,381,175 +$478,024,217 $79.76 221
2017 Q1 82,296,913 $4,218,075,181 +$357,641,470 $51.25 191
2016 Q4 79,901,866 $2,991,766,834 -$16,232,332 $37.44 203
2016 Q3 77,521,060 $5,253,109,562 +$213,492,546 $67.78 250
2016 Q2 74,050,576 $4,109,046,677 +$155,696,020 $55.49 240
2016 Q1 70,923,645 $4,451,021,161 +$295,037,172 $62.77 248
2015 Q4 66,039,006 $6,216,981,299 +$73,218,963 $94.14 258
2015 Q3 65,414,849 $5,256,534,541 -$57,051,793 $80.36 254
2015 Q2 65,565,499 $7,859,319,459 +$143,389,344 $119.87 274
2015 Q1 64,472,950 $6,731,323,619 +$672,355,194 $104.42 236
2014 Q4 57,984,886 $5,624,460,197 -$127,912,074 $97.00 214
2014 Q3 58,977,372 $4,606,139,951 +$102,404,978 $78.10 184
2014 Q2 57,779,618 $3,648,879,764 +$120,117,247 $63.17 190
2014 Q1 55,704,223 $3,739,161,613 +$8,742,143 $67.14 193