Alkermes plc
US ˙ NasdaqGS ˙ IE00B56GVS15

SecurityALKS / Alkermes plc
InstitutionSimplex Trading, Llc
Latest Disclosed Ownership13,138 shares
Latest Disclosed Value $ 464,559
Simplex Trading, Llc ownership in ALKS / Alkermes plc

On May 14, 2026 - Simplex Trading, Llc filed a 13F-HR form disclosing ownership of 13,138 shares of Alkermes plc (US:ALKS) valued at $464,560 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 0 shares of Alkermes plc. The current value of the position is $561,781 USD.

Simplex Trading, Llc has a history of taking positions in derivatives of the underlying security (ALKS) in the form of stock options. The firm currently holds call options representing 1,700 of underlying shares valued at $60,112 USD and put options representing 15,800 of underlying shares valued at $558,688 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

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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Institutional Put/Call Ratios
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In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

ALKS / Alkermes plc Historical Put/Call Ratio
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 COM G01767105 13,138 13,138 465 0.0001
2026-02-11 2025-12-31 13F ALKERMES COM G01767105 0 -14,667 -100.00 0 0.0000
2025-11-12 2025-09-30 13F ALKERMES COM G01767105 14,667 14,667 0 0.0002
2025-02-11 2024-12-31 13F ALKERMES COM G01767105 0 -5,173 -100.00 0 0.0000
2024-11-08 2024-09-30 13F ALKERMES COM G01767105 5,173 5,173 0 0.0001
2024-04-25 2024-03-31 13F ALKERMES COM G01767105 0 -9,004 -100.00 0 0.0000
2024-02-02 2023-12-31 13F ALKERMES COM G01767105 9,004 -14,991 -62.48 0 0.0002
2023-11-01 2023-09-30 13F ALKERMES COM G01767105 23,995 23,995 1 0.0005
2023-04-27 2023-03-31 13F ALKERMES COM G01767105 0 -874 -100.00 0 0.0000
2023-02-02 2022-12-31 13F ALKERMES COM G01767105 874 874 0 0.0000
2022-11-04 2022-09-30 13F ALKERMES COM G01767105 0 -2,980 -100.00 0 -100.00
2022-08-03 2022-06-30 13F ALKERMES COM G01767105 2,980 -7,469 -71.48 88 -67.88 0.0001
2022-05-02 2022-03-31 13F ALKERMES COM G01767105 10,449 -18,148 -63.46 274 -61.52 0.0003
2022-02-04 2021-12-31 13F ALKERMES COM G01767105 28,597 0 0.00 712 0.00 0.0007
2021-10-28 2021-09-30 13F ALKERMES COM G01767105 28,597 3,894 15.76 712 17.69 0.0007
2021-08-12 2021-06-30 13F ALKERMES COM G01767105 24,703 -34,371 -58.18 605 0.0006
2021-04-26 2021-03-31 13F ALKERMES COM G01767105 59,074 48,609 464.49 0 -100.00
2021-02-02 2020-12-31 13F ALKERMES COM G01767105 10,465 -30,412 -74.40 208 -69.28 0.0003
2020-10-14 2020-09-30 13F ALKERMES COM G01767105 40,877 -39,864 -49.37 677 -56.77 0.0009
2020-07-13 2020-06-30 13F ALKERMES COM G01767105 80,741 59,130 273.61 1,566 403.54 0.0025
2020-04-29 2020-03-31 13F ALKERMES COM G01767105 21,611 9,609 80.06 311 27.46 0.0005
2020-02-05 2019-12-31 13F ALKERMES COM G01767105 12,002 3,150 35.59 244 41.86 0.0005
2019-10-15 2019-09-30 13F ALKERMES COM G01767105 8,852 4,416 99.55 172 73.74 0.0005
2019-07-26 2019-06-30 13F ALKERMES COM G01767105 4,436 406 10.07 99 -32.65 0.0003
2019-04-18 2019-03-31 13F ALKERMES COM G01767105 4,030 -8,358 -67.47 147 -59.73 0.0004
2019-01-16 2018-12-31 13F ALKERMES COM G01767105 12,388 12,388 207.39 365 148.30 0.0011
2018-10-23 2018-09-30 13F ALKERMES COM G01767105 0 -2,629 -100.00 0 -100.00
2018-07-30 2018-06-30 13F ALKERMES COM G01767105 2,629 2,629 108 0.0004
2018-04-26 2018-03-31 13F ALKERMES COM G01767105 0 -47,300 -100.00 0 -100.00
2018-01-10 2017-12-31 13F ALKERMES COM G01767105 47,300 39,737 525.41 2,588 573.96 0.1114
2017-10-25 2017-09-30 13F ALKERMES COM G01767105 7,563 5,103 207.44 384 170.42 0.0157
2017-07-12 2017-06-30 13F ALKERMES COM G01767105 2,460 -4,723 -65.75 142 -66.19 0.0062
2017-04-21 2017-03-31 13F ALKERMES COM G01767105 7,183 -10,184 -58.64 420 -56.48 0.0182
2017-01-11 2016-12-31 13F ALKERMES COM G01767105 17,367 -3,666 -17.43 965 -2.43 0.0577
2016-10-07 2016-09-30 13F ALKERMES COM G01767105 21,033 18,712 806.20 989 889.00 0.0670
2016-07-18 2016-06-30 13F ALKERMES COM G01767105 2,321 -18,924 -89.08 100 -86.23 0.0067
2016-04-14 2016-03-31 13F ALKERMES COM G01767105 21,245 21,245 815.34 726 626.00 0.0579
2016-01-20 2015-12-31 13F ALKERMES COM G01767105 0 -15,314 -100.00 0 -100.00
2015-10-08 2015-09-30 13F ALKERMES COM G01767105 15,314 15,314 0.00 898 0.0658
2015-07-08 2015-06-30 13F ALKERMES COM G01767105 0 -3,301 -100.00 0 -100.00
2015-04-21 2015-03-31 13F ALKERMES COM G01767105 3,301 24 0.73 201 4.69 0.0234
2015-03-04 2014-12-31 13F ALKERMES COM G01767105 3,277 3,277 192 0.0233
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-14 2026-03-31 13F ALKERMES CALL Call 1,700 -65.31 60 -56.20 n/a n/a n/a
2026-02-11 2025-12-31 13F ALKERMES CALL Call 4,900 -24.62 137 n/a n/a n/a
2025-11-12 2025-09-30 13F ALKERMES CALL Call 6,500 622.22 0 n/a n/a n/a
2025-08-05 2025-06-30 13F ALKERMES CALL Call 900 -94.00 0 n/a n/a n/a
2025-05-12 2025-03-31 13F ALKERMES CALL Call 15,000 -45.45 0 n/a n/a n/a
2025-02-11 2024-12-31 13F ALKERMES CALL Call 27,500 13,650.00 1 n/a n/a n/a
2024-11-08 2024-09-30 13F ALKERMES CALL Call 200 -98.82 0 n/a n/a n/a
2024-07-25 2024-06-30 13F ALKERMES CALL Call 17,000 61.90 0 n/a n/a n/a
2024-04-25 2024-03-31 13F ALKERMES CALL Call 10,500 -77.52 0 n/a n/a n/a
2024-02-02 2023-12-31 13F ALKERMES CALL Call 46,700 14.18 0 -100.00 n/a n/a n/a
2023-11-01 2023-09-30 13F ALKERMES CALL Call 40,900 32.79 1 n/a n/a n/a
2023-08-04 2023-06-30 13F ALKERMES CALL Call 30,800 -50.64 1 -100.00 n/a n/a n/a
2023-04-27 2023-03-31 13F ALKERMES CALL Call 62,400 80.35 2 n/a n/a n/a
2023-02-02 2022-12-31 13F ALKERMES CALL Call 34,600 253.06 1 -100.00 n/a n/a n/a
2022-11-04 2022-09-30 13F ALKERMES CALL Call 9,800 58.06 218 18.48 n/a n/a n/a
2022-08-03 2022-06-30 13F ALKERMES CALL Call 6,200 34.78 184 52.07 n/a n/a n/a
2022-05-02 2022-03-31 13F ALKERMES CALL Call 4,600 -97.25 121 -96.89 n/a n/a n/a
2022-02-23 2021-12-31 13F/A ALKERMES CALL Call 167,300 1,449.07 3,891 1,351.87 n/a n/a n/a
2022-02-04 2021-12-31 13F ALKERMES CALL Call 10,800 268 n/a n/a n/a
2021-10-28 2021-09-30 13F ALKERMES CALL Call 10,800 -1.82 268 -0.37 n/a n/a n/a
2021-08-12 2021-06-30 13F ALKERMES CALL Call 11,000 1,758.11 269 n/a n/a n/a
2021-04-26 2021-03-31 13F ALKERMES CALL Call 592 286.93 0 -100.00 n/a n/a n/a
2021-02-02 2020-12-31 13F ALKERMES CALL Call 153 -8.93 305 9.71 n/a n/a n/a
2020-10-14 2020-09-30 13F ALKERMES CALL Call 168 9.09 278 -6.71 n/a n/a n/a
2020-07-13 2020-06-30 13F ALKERMES CALL Call 154 79.07 298 140.32 n/a n/a n/a
2020-04-29 2020-03-31 13F ALKERMES CALL Call 86 218.52 124 125.45 n/a n/a n/a
2020-02-05 2019-12-31 13F ALKERMES CALL Call 27 170.00 55 189.47 n/a n/a n/a
2019-10-15 2019-09-30 13F ALKERMES CALL Call 10 -80.39 19 -83.33 n/a n/a n/a
2019-07-26 2019-06-30 13F ALKERMES CALL Call 51 -86.47 114 -91.71 n/a n/a n/a
2019-04-18 2019-03-31 13F ALKERMES CALL Call 377 776.74 1,375 991.27 n/a n/a n/a
2019-01-16 2018-12-31 13F ALKERMES CALL Call 43 -69.50 126 -78.93 n/a n/a n/a
2018-10-23 2018-09-30 13F ALKERMES CALL Call 141 -23.37 598 -21.00 n/a n/a n/a
2018-07-30 2018-06-30 13F ALKERMES CALL Call 184 -99.44 757 -60.39 n/a n/a n/a
2018-04-26 2018-03-31 13F ALKERMES CALL Call 32,758 96,247.06 1,911 15,825.00 n/a n/a n/a
2018-01-10 2017-12-31 13F ALKERMES CALL Call 34 161.54 12 300.00 n/a n/a n/a
2017-10-25 2017-09-30 13F ALKERMES CALL Call 13 -82.43 3 -76.92 n/a n/a n/a
2017-07-12 2017-06-30 13F ALKERMES CALL Call 74 208.33 13 550.00 n/a n/a n/a
2017-04-21 2017-03-31 13F ALKERMES CALL Call 24 -89.29 2 -91.30 n/a n/a n/a
2017-01-11 2016-12-31 13F ALKERMES CALL Call 224 330.77 23 283.33 n/a n/a n/a
2016-10-07 2016-09-30 13F ALKERMES CALL Call 52 -35.80 6 -53.85 n/a n/a n/a
2016-07-18 2016-06-30 13F ALKERMES CALL Call 81 10.96 13 333.33 n/a n/a n/a
2016-04-14 2016-03-31 13F ALKERMES CALL Call 73 -50.34 3 -95.83 n/a n/a n/a
2016-01-20 2015-12-31 13F ALKERMES CALL Call 147 77.11 72 928.57 n/a n/a n/a
2015-10-08 2015-09-30 13F ALKERMES CALL Call 83 -34.65 7 -92.55 n/a n/a n/a
2015-07-08 2015-06-30 13F ALKERMES CALL Call 127 36.56 94 56.67 n/a n/a n/a
2015-04-21 2015-03-31 13F ALKERMES CALL Call 93 60 n/a n/a n/a
Disclosed Put Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share Price Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-14 2026-03-31 13F ALKERMES PUT Put 15,800 -44.37 559 -29.72 n/a n/a n/a
2026-02-11 2025-12-31 13F ALKERMES PUT Put 28,400 11.81 795 n/a n/a n/a
2025-11-12 2025-09-30 13F ALKERMES PUT Put 25,400 12,600.00 1 n/a n/a n/a
2025-08-05 2025-06-30 13F ALKERMES PUT Put 200 -98.04 0 n/a n/a n/a
2025-05-12 2025-03-31 13F ALKERMES PUT Put 10,200 85.45 0 n/a n/a n/a
2025-02-11 2024-12-31 13F ALKERMES PUT Put 5,500 358.33 0 n/a n/a n/a
2024-11-08 2024-09-30 13F ALKERMES PUT Put 1,200 -80.33 0 n/a n/a n/a
2024-07-25 2024-06-30 13F ALKERMES PUT Put 6,100 -70.39 0 n/a n/a n/a
2024-04-25 2024-03-31 13F ALKERMES PUT Put 20,600 -24.54 0 n/a n/a n/a
2024-02-02 2023-12-31 13F ALKERMES PUT Put 27,300 702.94 0 n/a n/a n/a
2023-11-01 2023-09-30 13F ALKERMES PUT Put 3,400 -80.00 0 n/a n/a n/a
2023-08-04 2023-06-30 13F ALKERMES PUT Put 17,000 -30.33 1 n/a n/a n/a
2023-04-27 2023-03-31 13F ALKERMES PUT Put 24,400 408.33 1 n/a n/a n/a
2023-02-02 2022-12-31 13F ALKERMES PUT Put 4,800 700.00 0 -100.00 n/a n/a n/a
2022-11-04 2022-09-30 13F ALKERMES PUT Put 600 -97.74 13 -98.35 n/a n/a n/a
2022-08-03 2022-06-30 13F ALKERMES PUT Put 26,500 92.03 789 117.36 n/a n/a n/a
2022-05-02 2022-03-31 13F ALKERMES PUT Put 13,800 -17.86 363 -6.92 n/a n/a n/a
2022-02-23 2021-12-31 13F/A ALKERMES PUT Put 16,800 2.44 390 -4.41 n/a n/a n/a
2022-02-04 2021-12-31 13F ALKERMES PUT Put 16,400 408 n/a n/a n/a
2021-10-28 2021-09-30 13F ALKERMES PUT Put 16,400 13.10 408 14.93 n/a n/a n/a
2021-08-12 2021-06-30 13F ALKERMES PUT Put 14,500 1,848.92 355 n/a n/a n/a
2021-04-26 2021-03-31 13F ALKERMES PUT Put 744 198.80 0 -100.00 n/a n/a n/a
2021-02-02 2020-12-31 13F ALKERMES PUT Put 249 -66.62 496 -59.87 n/a n/a n/a
2020-10-14 2020-09-30 13F ALKERMES PUT Put 746 1.91 1,236 -12.96 n/a n/a n/a
2020-07-13 2020-06-30 13F ALKERMES PUT Put 732 105.04 1,420 176.26 n/a n/a n/a
2020-04-29 2020-03-31 13F ALKERMES PUT Put 357 2,450.00 514 1,735.71 n/a n/a n/a
2020-02-05 2019-12-31 13F ALKERMES PUT Put 14 -22.22 28 -20.00 n/a n/a n/a
2019-10-15 2019-09-30 13F ALKERMES PUT Put 18 -60.00 35 -65.35 n/a n/a n/a
2019-07-26 2019-06-30 13F ALKERMES PUT Put 45 309.09 101 152.50 n/a n/a n/a
2019-04-18 2019-03-31 13F ALKERMES PUT Put 11 -93.57 40 -92.06 n/a n/a n/a
2019-01-16 2018-12-31 13F ALKERMES PUT Put 171 -13.20 504 -39.71 n/a n/a n/a
2018-10-23 2018-09-30 13F ALKERMES PUT Put 197 -40.84 836 -38.98 n/a n/a n/a
2018-07-30 2018-06-30 13F ALKERMES PUT Put 333 0.00 1,370 3,161.90 n/a n/a n/a
2018-04-26 2018-03-31 13F ALKERMES PUT Put 333 11.37 42 16.67 n/a n/a n/a
2018-01-10 2017-12-31 13F ALKERMES PUT Put 299 -40.91 36 -5.26 n/a n/a n/a
2017-10-25 2017-09-30 13F ALKERMES PUT Put 506 142.11 38 72.73 n/a n/a n/a
2017-07-12 2017-06-30 13F ALKERMES PUT Put 209 -28.91 22 -4.35 n/a n/a n/a
2017-04-21 2017-03-31 13F ALKERMES PUT Put 294 20.00 23 -23.33 n/a n/a n/a
2017-01-11 2016-12-31 13F ALKERMES PUT Put 245 -22.22 30 -44.44 n/a n/a n/a
2016-10-07 2016-09-30 13F ALKERMES PUT Put 315 668.29 54 157.14 n/a n/a n/a
2016-07-18 2016-06-30 13F ALKERMES PUT Put 41 -89.46 21 -90.23 n/a n/a n/a
2016-04-14 2016-03-31 13F ALKERMES PUT Put 389 347.13 215 2,971.43 n/a n/a n/a
2016-01-20 2015-12-31 13F ALKERMES PUT Put 87 -46.95 7 -96.59 n/a n/a n/a
2015-10-08 2015-09-30 13F ALKERMES PUT Put 164 2,633.33 205 10,150.00 n/a n/a n/a
2015-07-08 2015-06-30 13F ALKERMES PUT Put 6 200.00 2 100.00 n/a n/a n/a
2015-04-21 2015-03-31 13F ALKERMES PUT Put 2 1 n/a n/a n/a
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.