Alnylam Pharmaceuticals, Inc.
DE ˙ XTRA ˙ US02043Q1076
260,50 € ↑8,70 (3,46%)
2026-06-04
DEL PRIS
SecurityDE:DUL / Alnylam Pharmaceuticals, Inc.
InstitutionAssenagon Asset Management S.A.
Latest Disclosed Ownership128,896 shares
Latest Disclosed Value $ 42,647,820
Assenagon Asset Management S.A. reports 403.70% increase in ownership of DUL / Alnylam Pharmaceuticals, Inc.

On April 20, 2026 - Assenagon Asset Management S.A. filed a 13F-HR form disclosing ownership of 128,896 shares of Alnylam Pharmaceuticals, Inc. (DE:DUL) valued at $36,825,587 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 9, 2026 disclosing 25,590 shares of Alnylam Pharmaceuticals, Inc.. This represents a change in shares of 403.70% during the quarter. The current value of the position is $33,577,408 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)
2026-04-20 2026-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 128,896 103,306 403.70 42,648 319.14 0.0647
2026-01-09 2025-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 25,590 -54,791 -68.16 10,176 -72.24 0.0140
2025-10-07 2025-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 80,381 62,695 354.49 36,654 535.56 0.0501
2025-07-11 2025-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 17,686 11,281 176.13 5,767 233.55 0.0086
2025-04-15 2025-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 6,405 -13,513 -67.84 1,729 -63.10 0.0029
2025-01-14 2024-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 19,918 2,285 12.96 4,687 -3.36 0.0076
2024-10-23 2024-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 17,633 -105,163 -85.64 4,850 -83.75 0.0089
2024-07-18 2024-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 122,796 62,454 103.50 29,839 230.88 0.0664
2024-04-24 2024-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 60,342 46,176 325.96 9,018 232.64 0.0213
2024-01-17 2023-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 14,166 7,436 110.49 2,712 127.62 0.0072
2023-11-06 2023-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 6,730 -84,132 -92.59 1,192 -93.10 0.0037
2023-07-25 2023-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 90,862 -124,329 -57.78 17,258 -59.96 0.0597
2023-04-18 2023-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 215,191 207,364 2,649.34 43,107 4,310,600.00 0.1530
2023-01-12 2022-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 7,827 1,569 25.07 2 -99.92 0.0067
2022-10-27 2022-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 6,258 6,258 1,253 0.0048
2022-04-25 2022-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 0 -174,443 -100.00 0 -100.00
2022-02-01 2021-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 174,443 -159,846 -47.82 29,582 -53.13 0.0857
2021-10-19 2021-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 334,289 50,489 17.79 63,117 31.19 0.2018
2021-07-15 2021-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 283,800 160,032 129.30 48,110 175.31 0.1633
2021-04-26 2021-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 123,768 101,135 446.85 17,475 493.98 0.0709
2021-02-01 2020-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 22,633 -20,552 -47.59 2,942 -53.21 0.0128
2020-10-07 2020-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 43,185 -75,334 -63.56 6,288 -64.18 0.0353
2020-07-21 2020-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 118,519 94,607 395.65 17,554 574.38 0.1126
2020-04-17 2020-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 23,912 23,912 2,603 0.0208
2020-01-17 2019-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 0 -27,286 -100.00 0 -100.00
2019-10-16 2019-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 27,286 27,286 2,194 0.0147
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.