Alnylam Pharmaceuticals, Inc.
DE ˙ XTRA ˙ US02043Q1076
260,50 € ↑8,70 (3,46%)
2026-06-04
DEL PRIS
SecurityDE:DUL / Alnylam Pharmaceuticals, Inc.
InstitutionEventide Asset Management, Llc
Latest Disclosed Ownership1,111 shares
Latest Disclosed Value $ 351,206
Eventide Asset Management, Llc reports 96.74% decrease in ownership of DUL / Alnylam Pharmaceuticals, Inc.

On May 15, 2026 - Eventide Asset Management, Llc filed a 13F-HR form disclosing ownership of 1,111 shares of Alnylam Pharmaceuticals, Inc. (DE:DUL) valued at $317,413 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 34,035 shares of Alnylam Pharmaceuticals, Inc.. This represents a change in shares of -96.74% during the quarter. The current value of the position is $289,416 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 1,111 -32,924 -96.74 351 -97.41 0.0058
2026-02-13 2025-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 34,035 -67,704 -66.55 13,534 -70.82 0.2114
2025-11-14 2025-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 101,739 -24,163 -19.19 46,386 12.99 0.7626
2025-08-14 2025-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 125,902 -40,548 -24.36 41,053 -8.66 0.7193
2025-05-15 2025-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 166,450 -73,968 -30.77 44,943 -20.56 0.8953
2025-02-14 2024-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 240,418 16,085 7.17 56,573 -8.31 1.0302
2024-11-14 2024-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 224,333 137,333 157.85 61,698 191.84 1.0634
2024-08-13 2024-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 87,000 0 0.00 21,141 62.60 0.3619
2024-05-15 2024-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 87,000 0 0.00 13,002 -21.92 0.2039
2024-02-20 2023-12-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 87,000 87,000 16,653 0.2718
2024-02-14 2023-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 87,000 87,000 16,653 0.2718
2019-02-14 2018-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 0 -62,000 -100.00 0 -100.00
2018-11-14 2018-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 62,000 0 0.00 5,426 -11.14 0.1993
2018-08-14 2018-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 62,000 0 0.00 6,106 -17.31 0.2534
2018-05-17 2018-03-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 62,000 -28,000 -31.11 7,384 -35.43 0.3457
2018-05-15 2018-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 62,000 -28,000 7,384 0.3457
2018-02-14 2017-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 90,000 0 0.00 11,435 8.14 0.5961
2017-11-14 2017-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 90,000 0 0.00 10,574 47.31 0.5993
2017-08-14 2017-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 90,000 0 0.00 7,178 55.60 0.4469
2017-05-15 2017-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 90,000 0 0.00 4,613 36.88 0.3054
2017-02-14 2016-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 90,000 0 0.00 3,370 -44.75 0.2193
2016-11-14 2016-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 90,000 0 0.00 6,100 22.15 0.3724
2016-08-15 2016-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 90,000 0 0.00 4,994 -11.59 0.3056
2016-05-16 2016-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 90,000 0 0.00 5,649 -33.33 0.3156
2016-02-16 2015-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 90,000 19,300 27.30 8,473 49.15 0.4235
2015-11-13 2015-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 70,700 25,200 55.38 5,681 4.16 0.3301
2015-08-14 2015-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 45,500 3,600 8.59 5,454 24.66 0.2951
2015-05-14 2015-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 41,900 41,900 4,375 0.3292
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.