Alnylam Pharmaceuticals, Inc.
DE ˙ XTRA ˙ US02043Q1076
260,50 € ↑8,70 (3,46%)
2026-06-04
DEL PRIS
SecurityDE:DUL / Alnylam Pharmaceuticals, Inc.
InstitutionGuggenheim Capital Llc
Latest Disclosed Ownership37,114 shares
Latest Disclosed Value $ 12,279,909
Guggenheim Capital Llc reports 7.53% decrease in ownership of DUL / Alnylam Pharmaceuticals, Inc.

On May 15, 2026 - Guggenheim Capital Llc filed a 13F-HR form disclosing ownership of 37,114 shares of Alnylam Pharmaceuticals, Inc. (DE:DUL) valued at $10,603,470 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 40,135 shares of Alnylam Pharmaceuticals, Inc.. This represents a change in shares of -7.53% during the quarter. The current value of the position is $9,668,197 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.

Upgrade to unlock premium data and export to Excel .

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 37,114 -3,021 -7.53 12,280 -23.06 0.0474
2026-02-17 2025-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 40,135 31,510 365.33 15,960 305.77 0.1143
2025-11-13 2025-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 8,625 -2,024 -19.01 3,933 13.28 0.0285
2025-08-13 2025-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 10,649 -1,718 -13.89 3,473 3.98 0.0276
2025-05-14 2025-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 12,367 -416 -3.25 3,339 11.04 0.0307
2025-02-13 2024-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 12,783 -2,465 -16.17 3,008 -28.29 0.0244
2024-11-13 2024-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 15,248 -3,939 -20.53 4,194 -10.06 0.0293
2024-08-14 2024-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 19,187 -1,975 -9.33 4,662 47.44 0.0331
2024-05-14 2024-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 21,162 3,411 19.22 3,163 -6.92 0.0223
2024-02-14 2023-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 17,751 507 2.94 3,398 11.27 0.0257
2023-11-14 2023-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 17,244 -2,422 -12.32 3,054 -18.26 0.0263
2023-08-11 2023-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 19,666 -320 -1.60 3,735 -6.69 0.0293
2023-05-11 2023-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 19,986 -831 -3.99 4,004 -19.08 0.0337
2023-02-14 2022-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 20,817 1,560 8.10 4,947 28.36 0.0435
2022-11-14 2022-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 19,257 -6,092 -24.03 3,854 4.25 0.0353
2022-08-15 2022-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 25,349 -395 -1.53 3,697 -12.06 0.0292
2022-05-16 2022-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 25,744 -561 -2.13 4,204 -5.76 0.0253
2022-02-14 2021-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 26,305 2,461 10.32 4,461 -0.91 0.0233
2021-11-15 2021-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 23,844 -2,093 -8.07 4,502 2.39 0.0270
2021-08-13 2021-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 25,937 -3,501 -11.89 4,397 5.80 0.0259
2021-05-13 2021-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 29,438 -2,205 -6.97 4,156 1.05 0.0273
2021-02-16 2020-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 31,643 -6,401 -16.83 4,113 -25.74 0.0258
2020-11-13 2020-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 38,044 -7,104 -15.73 5,539 -17.17 0.0401
2020-08-14 2020-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 45,148 3,330 7.96 6,687 46.90 0.0517
2020-06-02 2020-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 41,818 -9,187 -18.01 4,552 -22.51 0.0458
2020-02-20 2019-12-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 51,005 315 0.62 5,874 44.11 0.0441
2020-02-14 2019-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 51,005 315 5,874 34,814.0238
2020-02-20 2019-09-30 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 50,690 -7,433 -12.79 4,076 -3.34 0.0326
2019-11-14 2019-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 50,690 -7,433 4,076 29,870.1236
2019-08-14 2019-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 58,123 -2,134 -3.54 4,217 -25.11 0.0343
2019-05-15 2019-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 60,257 -3,717 -5.81 5,631 20.73 0.0459
2019-02-14 2018-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 63,974 3,473 5.74 4,664 -11.92 0.0395
2018-11-14 2018-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 60,501 4,680 8.38 5,295 -3.69 0.0345
2018-08-14 2018-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 55,821 2,737 5.16 5,498 -13.05 0.0367
2018-05-15 2018-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 53,084 600 1.14 6,323 -5.16 0.0154
2018-02-14 2017-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 52,484 -32,983 -38.59 6,667 -33.60 0.0158
2017-11-14 2017-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 85,467 18,094 26.86 10,041 86.81 0.0236
2017-08-14 2017-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 67,373 -17,484 -20.60 5,375 23.59 0.0142
2017-05-15 2017-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 84,857 5,774 7.30 4,349 46.88 0.0118
2017-02-14 2016-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 79,083 4,565 6.13 2,961 -41.38 0.0085
2016-11-14 2016-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 74,518 -11,850 -13.72 5,051 5.38 0.0157
2016-08-15 2016-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 86,368 -4,294 -4.74 4,793 -15.78 0.0151
2016-05-16 2016-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 90,662 -23,340 -20.47 5,691 -46.97 0.0180
2016-02-16 2015-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 114,002 -28,541 -20.02 10,732 -6.31 0.0312
2015-11-16 2015-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 142,543 -2,220 -1.53 11,455 -33.99 0.0352
2015-08-14 2015-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 144,763 8,423 6.18 17,353 21.89 0.0428
2015-05-18 2015-03-31 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 136,340 22,323 19.58 14,237 28.73 0.0337
2015-05-15 2015-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 136,340 14,237
2015-02-17 2014-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 114,017 14,441 14.50 11,060 42.21 0.0277
2014-11-14 2014-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 99,576 -4,254 -4.10 7,777 18.57 0.0188
2014-08-14 2014-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 103,830 -10,627 -9.28 6,559 -14.64 0.0166
2014-05-16 2014-03-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 114,457 13,710 13.61 7,684 18.56 0.0219
2014-02-14 2013-12-31 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 100,747 -7,349 -6.80 6,481 -6.34 0.0197
2013-11-14 2013-09-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 108,096 -73,320 -40.42 6,920 23.00 0.0248
2013-08-22 2013-06-30 13F/A-1 ALNYLAM PHARMACEUTICALS COM 02043Q107 181,416 181,416 5,626 0.0237
2013-08-14 2013-06-30 13F ALNYLAM PHARMACEUTICALS COM 02043Q107 181,416 5,626 0.0237
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.