Alnylam Pharmaceuticals, Inc.
DE ˙ XTRA ˙ US02043Q1076
260,50 € ↑8,70 (3,46%)
2026-06-04
DEL PRIS
SecurityDE:DUL / Alnylam Pharmaceuticals, Inc.
InstitutionRockefeller Capital Management L.P.
Latest Disclosed Ownership6,437 shares
Latest Disclosed Value $ 2,129,903
Rockefeller Capital Management L.P. reports 20.77% decrease in ownership of DUL / Alnylam Pharmaceuticals, Inc.

On May 14, 2026 - Rockefeller Capital Management L.P. filed a 13F-HR form disclosing ownership of 6,437 shares of Alnylam Pharmaceuticals, Inc. (DE:DUL) valued at $1,839,051 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on March 16, 2026 disclosing 8,124 shares of Alnylam Pharmaceuticals, Inc.. This represents a change in shares of -20.77% during the quarter. The current value of the position is $1,676,838 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)
2026-05-14 2026-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 6,437 -1,687 -20.77 2,130 -34.09 0.0020
2026-03-16 2025-12-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 8,124 3,744 85.48 3,231 61.74 0.0058
2026-02-14 2025-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 360,349 355,969 3,231 0.0029
2025-11-14 2025-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 4,380 4,380 1,998 0.0039
2024-08-12 2024-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 0 -10,715 -100.00 0 -100.00
2024-05-14 2024-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 10,715 -358 -3.23 1,601 -24.45 0.0047
2024-02-14 2023-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 11,073 -2,111 -16.01 2,119 -9.21 0.0071
2023-11-14 2023-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 13,184 13,184 2,335 0.0090
2023-08-14 2023-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 0 -8,339 -100.00 0 -100.00
2023-05-16 2023-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 8,339 -2,332 -21.85 2 -99.96 0.0072
2023-03-06 2022-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 10,671 -1,010 -8.65 2,534 8.43 0.0127
2022-11-02 2022-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 11,681 -6,067 -34.18 2,337 -9.63 0.0121
2022-08-12 2022-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 17,748 -356,216 -95.25 2,586 -95.76 0.0137
2022-05-13 2022-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 373,964 -12,296 -3.18 61,062 -6.78 0.2945
2022-02-14 2021-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 386,260 68,160 21.43 65,500 9.06 0.3057
2021-11-12 2021-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 318,100 -79,209 -19.94 60,058 -10.83 0.3156
2021-08-10 2021-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 397,309 -3,251 -0.81 67,350 19.09 0.3794
2021-05-11 2021-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 400,560 11,815 3.04 56,553 11.94 0.3827
2021-02-12 2020-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 388,745 3,949 1.03 50,523 -9.82 0.3827
2020-11-13 2020-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 384,796 -699 -0.18 56,024 -1.88 0.5248
2020-08-12 2020-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 385,495 23,440 6.47 57,096 44.88 0.5974
2020-05-12 2020-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 362,055 -161,094 -30.79 39,410 -34.59 0.5170
2020-02-07 2019-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 523,149 -56,727 -9.78 60,252 29.20 0.7512
2019-11-12 2019-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 579,876 91,356 18.70 46,633 31.56 0.6326
2019-08-09 2019-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 488,520 863 0.18 35,447 -22.22 0.4942
2019-05-10 2019-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 487,657 1,108 0.23 45,571 28.46 0.6495
2019-02-12 2018-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 486,549 160,083 49.04 35,474 24.15 0.6217
2018-11-02 2018-09-30 13F Alnylam Pharmaceuticals Common 02043Q107 326,466 58,355 21.77 28,573 8.21 0.4337
2018-07-31 2018-06-30 13F Alnylam Pharmaceuticals Common 02043Q107 268,111 20,357 8.22 26,406 -10.51 0.4300
2018-05-09 2018-03-31 13F Alnylam Pharmaceuticals Common 02043Q107 247,754 247,754 29,507 0.4876
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.