Alnylam Pharmaceuticals, Inc.
DE ˙ XTRA ˙ US02043Q1076
251,80 € ↑6,70 (2,73%)
2026-06-03
DEL PRIS
SecurityDE:DUL / Alnylam Pharmaceuticals, Inc.
InstitutionMorgan Stanley
Latest Disclosed Ownership1,002,681 shares
Latest Disclosed Value $ 331,758,096
Morgan Stanley reports 3.35% increase in ownership of DUL / Alnylam Pharmaceuticals, Inc.

On May 15, 2026 - Morgan Stanley filed a 13F-HR form disclosing ownership of 1,002,681 shares of Alnylam Pharmaceuticals, Inc. (DE:DUL) valued at $286,465,962 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on May 27, 2026 disclosing 970,157 shares of Alnylam Pharmaceuticals, Inc.. This represents a change in shares of 3.35% during the quarter. The current value of the position is $252,475,076 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,002,681 32,524 3.35 331,758 -14.00 0.0200
2026-05-27 2025-12-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 970,157 244,096 33.62 385,784 16.52 0.0230
2026-02-13 2025-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 970,157 244,096 385,784 0.0230
2026-05-27 2025-09-30 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 726,061 -44,907 -5.82 331,085 31.69 0.0200
2025-11-14 2025-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 726,061 -44,907 331,085 0.0200
2025-08-15 2025-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 770,968 129,203 20.13 251,406 45.08 0.0164
2025-05-15 2025-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 641,765 -85,459 -11.75 173,290 1.27 0.0124
2025-05-15 2024-12-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 727,224 108,661 17.57 171,124 0.59 0.0120
2025-02-14 2024-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 727,224 108,661 171,124 0.0120
2025-05-14 2024-09-30 13F/A-2 ALNYLAM PHARMACEUTICALS COM 02043Q107 618,563 -122,951 -16.58 170,124 -5.59 0.0123
2025-02-14 2024-09-30 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 618,563 -122,951 170,124 0.0123
2024-11-14 2024-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 618,563 -122,951 170,124 0.0015
2025-05-14 2024-06-30 13F/A-2 ALNYLAM PHARMACEUTICALS COM 02043Q107 741,514 66,233 9.81 180,189 78.54 0.0139
2024-10-17 2024-06-30 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 741,514 66,233 180,189 0.0139
2024-08-14 2024-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 741,514 66,233 180,189 0.0139
2024-10-17 2024-03-31 13F/A-2 ALNYLAM PHARMACEUTICALS COM 02043Q107 675,281 -131,314 -16.28 100,921 -34.63 0.0081
2024-08-16 2024-03-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 675,281 -131,314 100,921 0.0009
2024-05-15 2024-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 675,281 -131,314 100,921 0.0081
2024-08-16 2023-12-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 806,595 -402,788 -33.31 154,391 -27.92 0.0136
2024-02-13 2023-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 806,595 -402,788 154,391 0.0136
2023-11-15 2023-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,209,383 -671,423 -35.70 214,182 -40.05 0.0218
2023-08-14 2023-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,880,806 649,991 52.81 357,241 44.89 0.0352
2023-05-15 2023-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,230,815 -159,825 -11.49 246,557 -25.40 0.0264
2023-02-14 2022-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,390,640 -108,119 -7.21 330,486 10.16 0.0375
2022-11-14 2022-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,498,759 370,144 32.80 299,992 82.25 0.0409
2022-10-27 2022-06-30 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 1,128,615 279,958 32.99 164,608 18.78 0.0214
2022-08-15 2022-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,128,615 279,958 164,608 0.0043
2022-10-27 2022-03-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 848,657 -217,032 -20.37 138,578 -23.32 0.0187
2022-05-13 2022-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 848,657 -217,032 138,578 0.0187
2022-02-14 2021-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,065,689 -815,190 -43.34 180,719 -49.11 0.0223
2021-11-15 2021-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,880,879 -1,772 -0.09 355,128 11.27 0.0478
2021-08-23 2021-06-30 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 1,882,651 96,697 5.41 319,147 26.57 0.0421
2021-08-16 2021-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,882,651 96,697 319,147 0.0088
2021-05-17 2021-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,785,954 94,114 5.56 252,160 14.68 0.0370
2021-02-16 2020-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,691,840 171,490 11.28 219,889 -0.67 0.0340
2020-11-13 2020-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,520,350 10,479 0.69 221,363 -1.01 0.0428
2020-08-14 2020-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,509,871 124,671 9.00 223,627 48.31 0.0495
2020-05-26 2020-03-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 1,385,200 -155,616 -10.10 150,780 -15.03 0.0410
2020-05-15 2020-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,385,200 -155,616 150,780 11,583.0472
2020-02-14 2019-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,540,816 177,298 13.00 177,456 61.83 0.0413
2019-11-14 2019-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,363,518 26,397 1.97 109,655 13.02 0.0290
2019-08-14 2019-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,337,121 116,760 9.57 97,021 -14.93 0.0258
2019-05-15 2019-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,220,361 37,462 3.17 114,043 32.23 0.0323
2019-02-14 2018-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,182,899 -54,587 -4.41 86,245 -20.37 0.0258
2019-04-23 2018-09-30 13F/A-2 ALNYLAM PHARMACEUTICALS COM 02043Q107 1,237,486 -19,556 -1.56 108,304 -12.52 0.0271
2018-11-20 2018-09-30 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 1,237,486 0 108,304 0.0271
2018-11-14 2018-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,237,486 -19,556 108,304
2019-04-23 2018-06-30 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 1,257,042 -3,381 -0.27 123,807 -17.53 0.0334
2018-08-14 2018-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,257,042 -3,381 123,807
2019-04-23 2018-03-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 1,260,423 91,652 7.84 150,116 1.09 0.0417
2018-05-14 2018-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,260,423 91,652 150,116
2019-04-23 2017-12-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 1,168,771 188,948 19.28 148,492 28.99 0.0406
2018-02-14 2017-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,168,771 188,948 148,492
2017-11-14 2017-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 979,823 -37,708 -3.71 115,119 41.85 0.0345
2017-08-11 2017-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,017,531 315,795 45.00 81,157 125.67 0.0245
2017-05-22 2017-03-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 701,736 -110,448 -13.60 35,963 18.27 0.0111
2017-05-12 2017-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 701,736 35,963
2017-02-22 2016-12-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 812,184 -28,228 -3.36 30,408 -46.62 0.0100
2017-02-13 2016-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 812,184 30,408
2016-11-10 2016-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 840,412 -34,692 -3.96 56,964 17.31 0.0195
2016-08-12 2016-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 875,104 -203,778 -18.89 48,559 -28.29 0.0175
2016-05-12 2016-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,078,882 -18,043 -1.64 67,720 -34.42 0.0261
2016-02-09 2015-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,096,925 -115,371 -9.52 103,264 6.00 0.0374
2016-02-08 2015-09-30 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 1,212,296 -84,961 -6.55 97,419 -37.35 0.0360
2015-11-09 2015-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,212,296 97,419
2015-08-12 2015-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,297,257 -102,268 -7.31 155,503 6.41 0.0539
2015-05-14 2015-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,399,525 24,119 1.75 146,139 9.54 0.0538
2015-02-13 2014-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,375,406 513,571 59.59 133,413 98.21 0.0488
2014-12-16 2014-09-30 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 861,835 -5,784 -0.67 67,310 22.81 0.0259
2014-11-14 2014-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 861,835 67,310
2014-08-12 2014-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 867,619 128,433 17.37 54,807 10.43 0.0937
2014-05-13 2014-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 739,186 -2,379 -0.32 49,630 4.09 0.0208
2014-02-13 2013-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 741,565 550,847 288.83 47,682 290.58 0.0203
2013-11-13 2013-09-30 13F ALNYLAM PHARM COM 02043Q107 190,718 137,477 258.22 12,208 639.88 0.0058
2013-08-08 2013-06-30 13F ALNYLAM PHARM COM 02043Q107 53,241 53,241 1,650 0.0008
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.