Alnylam Pharmaceuticals, Inc.
US ˙ NasdaqGS ˙ US02043Q1076

SecurityALNY / Alnylam Pharmaceuticals, Inc.
InstitutionShell Asset Management Co
Latest Disclosed Ownership2,779 shares
Latest Disclosed Value $ 1,267
Shell Asset Management Co reports 61.71% decrease in ownership of ALNY / Alnylam Pharmaceuticals, Inc.

On November 7, 2025 - Shell Asset Management Co filed a 13F-HR form disclosing ownership of 2,779 shares of Alnylam Pharmaceuticals, Inc. (US:ALNY) valued at $1,267,224 USD as of September 30, 2025. The entity filed a previous 13F-HR on July 23, 2025 disclosing 7,257 shares of Alnylam Pharmaceuticals, Inc.. This represents a change in shares of -61.71% during the quarter. The current value of the position is $843,816 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)
2025-11-07 2025-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 2,779 -4,478 -61.71 1 -50.00 0.1273
2025-07-23 2025-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 7,257 1,602 28.33 2 100.00 0.0817
2025-05-14 2025-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 5,655 -337 -5.62 2 0.00 0.0725
2025-02-14 2024-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 5,992 -205 -3.31 1 0.00 0.0616
2024-11-07 2024-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 6,197 3,224 108.44 2 0.0750
2024-07-25 2024-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 2,973 -828 -21.78 1 0.0329
2024-02-14 2023-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 3,801 -1,031 -21.34 1 0.0336
2023-11-08 2023-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 4,832 -77 -1.57 1 0.0354
2023-07-28 2023-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 4,909 -99 -1.98 1 -100.00 0.0368
2023-05-15 2023-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 5,008 492 10.89 1 0.00 0.0416
2023-02-07 2022-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 4,516 -347 -7.14 1 -99.90 0.0470
2022-11-14 2022-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 4,863 -1,898 -28.07 973 -1.32 0.0379
2022-08-09 2022-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 6,761 639 10.44 986 -1.40 0.0292
2022-05-04 2022-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 6,122 314 5.41 1,000 1.52 0.0236
2022-02-09 2021-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 5,808 2,053 54.67 985 38.93 0.0202
2021-11-04 2021-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 3,755 -172 -4.38 709 6.46 0.0159
2021-08-12 2021-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 3,927 960 32.36 666 58.95 0.0129
2021-05-10 2021-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 2,967 153 5.44 419 14.48 0.0084
2021-02-16 2020-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 2,814 -59 -2.05 366 -12.44 0.0076
2020-11-13 2020-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 2,873 -316 -9.91 418 -11.44 0.0097
2020-08-10 2020-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 3,189 -1,315 -29.20 472 -3.67 0.0118
2020-05-11 2020-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 4,504 100 2.27 490 -3.35 0.0137
2020-02-13 2019-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 4,404 -1,288 -22.63 507 10.70 0.0109
2019-11-12 2019-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 5,692 0 0.00 458 10.90 0.0105
2019-08-12 2019-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 5,692 1,730 43.66 413 11.62 0.0091
2019-05-09 2019-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 3,962 0 0.00 370 28.03 0.0082
2019-02-13 2018-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 3,962 -1,954 -33.03 289 -44.21 0.0072
2018-11-13 2018-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 5,916 -3,946 -40.01 518 -46.65 0.0102
2018-08-10 2018-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 9,862 -2,060 -17.28 971 -31.62 0.0199
2018-05-14 2018-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 11,922 -11,849 -49.85 1,420 -52.98 0.0283
2018-02-09 2017-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 23,771 23,771 3,020 0.0599
2017-01-10 2016-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 0 -3,345 -100.00 0 -100.00
2016-10-28 2016-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 3,345 0 0.00 227 22.04 0.0054
2016-07-25 2016-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 3,345 -368 -9.91 186 -20.17 0.0043
2016-05-11 2016-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 3,713 201 5.72 233 -29.61 0.0056
2016-02-05 2015-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 3,512 3,512 0.00 331 0.0078
2015-10-13 2015-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 0 -6,049 -100.00 0 -100.00
2015-07-30 2015-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 6,049 -251 -3.98 725 79.01 0.0145
2014-02-03 2013-12-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 6,300 -7,000 -52.63 405 -52.41 0.0069
2014-01-27 2013-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 6,300 405
2013-10-28 2013-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 13,300 0 0.00 851 106.55 0.0156
2013-08-01 2013-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 13,300 13,300 412 0.0078
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.