Alkermes plc
US ˙ NasdaqGS ˙ IE00B56GVS15

SecurityALKS / Alkermes plc
InstitutionS&co Inc
Latest Disclosed Ownership244,760 shares
Latest Disclosed Value $ 8,654
S&co Inc reports 21.31% increase in ownership of ALKS / Alkermes plc

On May 7, 2026 - S&co Inc filed a 13F-HR form disclosing ownership of 244,760 shares of Alkermes plc (US:ALKS) valued at $8,654,714 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 5, 2026 disclosing 201,760 shares of Alkermes plc. This represents a change in shares of 21.31% during the quarter. The current value of the position is $10,465,938 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)
2026-05-07 2026-03-31 13F ALKERMES COM G01767105 244,760 43,000 21.31 9 60.00 0.5369
2026-02-05 2025-12-31 13F ALKERMES COM G01767105 201,760 550 0.27 6 -16.67 0.3506
2025-11-06 2025-09-30 13F ALKERMES COM G01767105 201,210 -19,375 -8.78 6 0.00 0.3695
2025-08-07 2025-06-30 13F ALKERMES COM G01767105 220,585 -1,375 -0.62 6 -14.29 0.4046
2025-05-08 2025-03-31 13F ALKERMES COM G01767105 221,960 7,495 3.49 7 16.67 0.4919
2025-02-07 2024-12-31 13F ALKERMES COM G01767105 214,465 -250 -0.12 6 0.00 0.4186
2024-11-07 2024-09-30 13F ALKERMES COM G01767105 214,715 0 0.00 6 20.00 0.3926
2024-08-08 2024-06-30 13F ALKERMES COM G01767105 214,715 4,000 1.90 5 0.00 0.3609
2024-05-09 2024-03-31 13F ALKERMES COM G01767105 210,715 37,570 21.70 6 25.00 0.4017
2024-02-12 2023-12-31 13F ALKERMES COM G01767105 173,145 20,145 13.17 5 0.00 0.3683
2023-11-09 2023-09-30 13F ALKERMES COM G01767105 153,000 0 0.00 4 0.00 0.3519
2023-08-08 2023-06-30 13F ALKERMES COM G01767105 153,000 0 0.00 5 0.00 0.3858
2023-05-09 2023-03-31 13F ALKERMES COM G01767105 153,000 0 0.00 4 33.33 0.3662
2023-02-07 2022-12-31 13F ALKERMES COM G01767105 153,000 0 0.00 4 -99.91 0.3500
2022-11-09 2022-09-30 13F ALKERMES COM G01767105 153,000 0 0.00 3,416 -25.04 0.3076
2022-08-09 2022-06-30 13F ALKERMES COM G01767105 153,000 0 0.00 4,557 13.22 0.3831
2022-05-05 2022-03-31 13F ALKERMES COM G01767105 153,000 0 0.00 4,025 13.13 0.2825
2022-02-08 2021-12-31 13F ALKERMES COM G01767105 153,000 0 0.00 3,558 -24.59 0.2513
2021-11-09 2021-09-30 13F ALKERMES COM G01767105 153,000 0 0.00 4,718 25.78 0.3678
2021-07-14 2021-06-30 13F ALKERMES COM G01767105 153,000 800 0.53 3,751 31.94 0.2929
2021-04-23 2021-03-31 13F ALKERMES COM G01767105 152,200 0 0.00 2,843 -6.36 0.2392
2021-01-28 2020-12-31 13F ALKERMES COM G01767105 152,200 10,000 7.03 3,036 28.86 0.2711
2020-12-11 2020-09-30 13F ALKERMES COM G01767105 142,200 0 0.00 2,356 -14.61 0.2349
2020-12-16 2020-06-30 13F ALKERMES COM G01767105 142,200 106,000 292.82 2,759 428.54 0.3031
2020-04-28 2020-03-31 13F ALKERMES COM G01767105 36,200 20,000 123.46 522 58.18 0.0697
2020-01-24 2019-12-31 13F ALKERMES COM G01767105 16,200 0 0.00 330 4.43 0.0344
2019-10-29 2019-09-30 13F ALKERMES COM G01767105 16,200 7,000 76.09 316 52.66 0.0350
2019-07-23 2019-06-30 13F ALKERMES COM G01767105 9,200 1,000 12.20 207 -30.77 0.0227
2019-04-24 2019-03-31 13F ALKERMES COM G01767105 8,200 0 0.00 299 23.55 0.0333
2019-01-29 2018-12-31 13F ALKERMES COM G01767105 8,200 0 0.00 242 -30.46 0.0307
2018-11-05 2018-09-30 13F ALKERMES COM G01767105 8,200 0 0.00 348 2.96 0.0390
2018-07-27 2018-06-30 13F ALKERMES COM G01767105 8,200 0 0.00 338 -28.84 0.0407
2018-05-02 2018-03-31 13F ALKERMES COM G01767105 8,200 0 0.00 475 5.79 0.0598
2018-01-22 2017-12-31 13F ALKERMES COM G01767105 8,200 0 0.00 449 7.67 0.0557
2017-11-02 2017-09-30 13F ALKERMES COM G01767105 8,200 0 0.00 417 -12.21 0.0533
2017-07-28 2017-06-30 13F ALKERMES COM G01767105 8,200 0 0.00 475 -1.04 0.0628
2017-04-07 2017-03-31 13F ALKERMES COM G01767105 8,200 0 0.00 480 5.26 0.0653
2017-01-27 2016-12-31 13F/A-1 ALKERMES COM G01767105 8,200 -600 -6.82 456 10.14 0.0660
2016-10-28 2016-09-30 13F ALKERMES COM G01767105 8,800 -1,000 -10.20 414 -2.36 0.0622
2016-07-21 2016-06-30 13F ALKERMES COM G01767105 9,800 400 4.26 424 32.09 0.0656
2016-04-29 2016-03-31 13F ALKERMES COM G01767105 9,400 -2,350 -20.00 321 -65.59 0.0520
2016-01-27 2015-12-31 13F ALKERMES COM G01767105 11,750 4,750 67.86 933 127.01 0.1567
2015-10-28 2015-09-30 13F ALKERMES COM G01767105 7,000 0 0.00 411 -8.67 0.0708
2015-07-13 2015-06-30 13F ALKERMES COM G01767105 7,000 0 0.00 450 5.39 0.0658
2015-04-27 2015-03-31 13F ALKERMES COM G01767105 7,000 0 0.00 427 4.15 0.0607
2015-01-20 2014-12-31 13F ALKERMES COM G01767105 7,000 0 0.00 410 36.67 0.0594
2014-10-31 2014-09-30 13F ALKERMES COM G01767105 7,000 0 0.00 300 -14.77 0.0459
2014-07-24 2014-06-30 13F ALKERMES COM G01767105 7,000 0 0.00 352 13.92 0.0489
2014-04-28 2014-03-31 13F ALKERMES COM G01767105 7,000 0 0.00 309 8.42 0.0462
2014-02-07 2013-12-31 13F ALKERMES COM G01767105 7,000 0 0.00 285 21.28 0.0476
2013-10-22 2013-09-30 13F ALKERMES COM G01767105 7,000 0 0.00 235 16.92 0.0412
2013-07-24 2013-06-30 13F ALKERMES COM G01767105 7,000 7,000 201 0.0305
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.