Alkermes plc
US ˙ NasdaqGS ˙ IE00B56GVS15

SecurityALKS / Alkermes plc
InstitutionNorthern Trust Corp
Latest Disclosed Ownership1,697,082 shares
Latest Disclosed Value $ 60,008,821
Northern Trust Corp reports 2.64% increase in ownership of ALKS / Alkermes plc

On May 14, 2026 - Northern Trust Corp filed a 13F-HR form disclosing ownership of 1,697,082 shares of Alkermes plc (US:ALKS) valued at $60,008,820 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 1,653,475 shares of Alkermes plc. This represents a change in shares of 2.64% during the quarter. The current value of the position is $72,567,226 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 ALKERMES SHS G01767105 1,697,082 43,607 2.64 60,009 29.71 0.0016
2026-02-17 2025-12-31 13F ALKERMES SHS G01767105 1,653,475 -112,705 -6.38 46,264 -12.68 0.0012
2025-11-14 2025-09-30 13F ALKERMES SHS G01767105 1,766,180 -47,429 -2.62 52,985 2.12 0.0015
2025-08-13 2025-06-30 13F ALKERMES SHS G01767105 1,813,609 -63,281 -3.37 51,887 -16.28 0.0071
2025-05-13 2025-03-31 13F ALKERMES SHS G01767105 1,876,890 -35,242 -1.84 61,975 12.70 0.0092
2025-02-14 2024-12-31 13F ALKERMES SHS G01767105 1,912,132 167,452 9.60 54,993 12.61 0.0078
2024-11-13 2024-09-30 13F ALKERMES COM G01767105 1,744,680 -28,071 -1.58 48,834 14.30 0.0080
2024-08-14 2024-06-30 13F ALKERMES COM G01767105 1,772,751 -24,167 -1.34 42,723 -12.17 0.0072
2024-05-14 2024-03-31 13F ALKERMES COM G01767105 1,796,918 -46,913 -2.54 48,643 -4.90 0.0084
2024-02-13 2023-12-31 13F ALKERMES COM G01767105 1,843,831 154,944 9.17 51,148 8.12 0.0093
2023-11-13 2023-09-30 13F ALKERMES COM G01767105 1,688,887 13,545 0.81 47,306 -9.79 0.0092
2023-08-11 2023-06-30 13F ALKERMES COM G01767105 1,675,342 41,512 2.54 52,438 13.85 0.0101
2023-05-15 2023-03-31 13F ALKERMES COM G01767105 1,633,830 18,911 1.17 46,058 9.15 0.0091
2023-02-13 2022-12-31 13F ALKERMES COM G01767105 1,614,919 13,369 0.83 42,198 17.99 0.0089
2022-11-14 2022-09-30 13F ALKERMES COM G01767105 1,601,550 -13,329 -0.83 35,762 -25.66 0.0082
2022-08-12 2022-06-30 13F ALKERMES COM G01767105 1,614,879 -17,703 -1.08 48,108 12.00 0.0103
2022-05-13 2022-03-31 13F ALKERMES COM G01767105 1,632,582 -81,979 -4.78 42,953 7.70 0.0076
2022-02-08 2021-12-31 13F ALKERMES SHS G01767105 1,714,561 -30,369 -1.74 39,881 -25.89 0.0065
2021-11-15 2021-09-30 13F ALKERMES SHS G01767105 1,744,930 -38,419 -2.15 53,813 23.06 0.0095
2021-08-13 2021-06-30 13F ALKERMES SHS G01767105 1,783,349 1,026,700 135.69 43,729 209.39 0.0077
2021-05-12 2021-03-31 13F ALKERMES SHS G01767105 756,649 17,924 2.43 14,134 -4.10 0.0026
2021-02-11 2020-12-31 13F ALKERMES SHS G01767105 738,725 -11,768 -1.57 14,738 18.52 0.0029
2020-11-16 2020-09-30 13F ALKERMES SHS G01767105 750,493 -31,949 -4.08 12,435 -18.10 0.0027
2020-08-14 2020-06-30 13F ALKERMES COM G01767105 782,442 -18,806 -2.35 15,183 31.41 0.0036
2020-05-14 2020-03-31 13F ALKERMES SHS G01767105 801,248 64,416 8.74 11,554 -23.13 0.0033
2020-02-14 2019-12-31 13F ALKERMES SHS G01767105 736,832 -189,210 -20.43 15,030 -16.81 0.0034
2019-11-13 2019-09-30 13F ALKERMES COM G01767105 926,042 -6,601 -0.71 18,067 -14.06 0.0043
2019-08-13 2019-06-30 13F ALKERMES SHS G01767105 932,643 14,451 1.57 21,022 -37.26 0.0050
2019-05-13 2019-03-31 13F ALKERMES SHS G01767105 918,192 4,276 0.47 33,505 24.23 0.0083
2019-02-12 2018-12-31 13F ALKERMES SHS G01767105 913,916 58,444 6.83 26,970 -25.71 0.0076
2018-11-14 2018-09-30 13F ALKERMES SHS G01767105 855,472 -20,528 -2.34 36,305 0.69 0.0089
2018-09-18 2018-06-30 13F/A-1 ALKERMES SHS G01767105 876,000 25,526 3.00 36,056 -26.85 0.0092
2018-08-14 2018-06-30 13F ALKERMES SHS G01767105 886,642 36,168 36,494
2018-05-09 2018-03-31 13F ALKERMES SHS G01767105 850,474 -8,279 -0.96 49,293 4.88 0.0128
2018-02-14 2017-12-31 13F ALKERMES SHS G01767105 858,753 450 0.05 47,000 7.71 0.0119
2017-11-13 2017-09-30 13F ALKERMES SHS G01767105 858,303 3,487 0.41 43,636 -11.94 0.0114
2017-08-11 2017-06-30 13F ALKERMES COM G01767105 854,816 7,845 0.93 49,554 0.01 0.0139
2017-05-12 2017-03-31 13F ALKERMES COM G01767105 846,971 20,628 2.50 49,548 7.88 0.0143
2017-02-13 2016-12-31 13F ALKERMES COM G01767105 826,343 19,536 2.42 45,927 21.04 0.0141
2016-11-09 2016-09-30 13F ALKERMES COM G01767105 806,807 32,023 4.13 37,943 13.31 0.0118
2016-08-12 2016-06-30 13F ALKERMES SHS G01767105 774,784 42,806 5.85 33,486 28.26 0.0109
2016-08-19 2016-03-31 13F/A-1 ALKERMES SHS G01767105 731,978 29,431 4.19 26,108 -53.19 0.0087
2016-05-13 2016-03-31 13F Alkermes COMM G01767105 731,978 25,027
2016-02-12 2015-12-31 13F Alkermes COMM G01767105 702,547 -175,496 -19.99 55,770 8.26 0.0185
2015-11-12 2015-09-30 13F Alkermes COMM G01767105 878,043 878,043 0.00 51,515 0.0172
2015-08-13 2015-06-30 13F Alkermes COMM G01767105 0 -996,203 -100.00 0 -100.00
2015-05-14 2015-03-31 13F Alkermes COMM G01767105 996,203 240,209 31.77 60,737 37.19 0.0183
2015-02-12 2014-12-31 13F Alkermes COM G01767105 755,994 75,763 11.14 44,271 51.82 0.0134
2014-11-13 2014-09-30 13F ALKERMES COM G01767105 680,231 75,917 12.56 29,161 -4.13 0.0092
2014-08-14 2014-06-30 13F ALKERMES COM G01767105 604,314 -5,625 -0.92 30,416 13.10 0.0095
2014-05-14 2014-03-31 13F ALKERMES COM G01767105 609,939 9,695 1.62 26,892 10.19 0.0085
2014-02-21 2013-12-31 13F/A-1 ALKERMES COM G01767105 600,244 11,984 2.04 24,406 23.41 0.0078
2014-02-12 2013-12-31 13F ALKERMES COM G01767105 600,244 24,406
2013-11-13 2013-09-30 13F ALKERMES COM G01767105 588,260 -763,544 -56.48 19,777 -48.99 0.0070
2013-08-09 2013-06-30 13F ALKERMES COM G01767105 1,351,804 1,351,804 38,770 0.0140
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.