Alnylam Pharmaceuticals, Inc.
US ˙ NasdaqGS ˙ US02043Q1076

SecurityALNY / Alnylam Pharmaceuticals, Inc.
InstitutionPrudential Plc
Latest Disclosed Ownership7,696 shares
Latest Disclosed Value $ 2,546,376
Prudential Plc reports 1.70% decrease in ownership of ALNY / Alnylam Pharmaceuticals, Inc.

On May 14, 2026 - Prudential Plc filed a 13F-HR form disclosing ownership of 7,696 shares of Alnylam Pharmaceuticals, Inc. (US:ALNY) valued at $2,546,376 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 7,829 shares of Alnylam Pharmaceuticals, Inc.. This represents a change in shares of -1.70% during the quarter. The current value of the position is $2,251,696 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 7,696 -133 -1.70 2,546 -18.21 0.0110
2026-02-11 2025-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 7,829 133 1.73 3,113 -11.29 0.0247
2025-11-14 2025-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 7,696 3,584 87.16 3,509 161.87 0.0258
2025-08-12 2025-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 4,112 2,065 100.88 1,341 142.75 0.0081
2025-05-13 2025-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 2,047 -2,233 -52.17 553 -45.18 0.0028
2025-02-13 2024-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 4,280 1,264 41.91 1,007 21.47 0.0051
2024-11-13 2024-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 3,016 143 4.98 829 18.77 0.0042
2024-08-07 2024-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 2,873 0 0.00 698 62.70 0.0047
2024-05-14 2024-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 2,873 -1,994 -40.97 429 -53.92 0.0033
2024-02-14 2023-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 4,867 -11 -0.23 932 7.88 0.0095
2023-11-13 2023-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 4,878 -761 -13.50 864 -19.42 0.0096
2023-08-14 2023-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 5,639 -81 -1.42 1,071 -6.46 0.0125
2023-05-12 2023-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 5,720 6 0.11 1,146 -15.62 0.0134
2023-02-09 2022-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 5,714 3,617 172.48 1,358 223.10 0.0170
2022-11-14 2022-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 2,097 316 17.74 420 61.54 0.0066
2022-08-12 2022-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,781 0 0.00 260 -10.65 0.0047
2022-05-13 2022-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 1,781 1,781 291 0.0042
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.