Prothena Corporation plc
DE ˙ DB ˙ IE00B91XRN20
7,74 € ↑0,39 (5,30%)
2026-06-04
AKTIENPREIS
SecurityDE:0PT / Prothena Corporation plc
InstitutionMorgan Stanley
Latest Disclosed Ownership1,230,448 shares
Latest Disclosed Value $ 11,959,961
Morgan Stanley reports 1.31% decrease in ownership of 0PT / Prothena Corporation plc

On May 15, 2026 - Morgan Stanley filed a 13F-HR form disclosing ownership of 1,230,448 shares of Prothena Corporation plc (DE:0PT) valued at $10,089,674 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on May 27, 2026 disclosing 1,246,775 shares of Prothena Corporation plc. This represents a change in shares of -1.31% during the quarter. The current value of the position is $9,528,589 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 PROTHENA CORP SHS G72800108 1,230,448 -16,327 -1.31 11,960 0.45 0.0007
2026-05-27 2025-12-31 13F/A-1 PROTHENA CORP SHS G72800108 1,246,775 447,101 55.91 11,907 52.56 0.0007
2026-02-13 2025-12-31 13F PROTHENA CORP SHS G72800108 1,246,775 447,101 11,907 0.0007
2026-05-27 2025-09-30 13F/A-1 PROTHENA CORP SHS G72800108 799,674 -153,582 -16.11 7,805 34.88 0.0005
2025-11-14 2025-09-30 13F PROTHENA CORP SHS G72800108 799,674 -153,582 7,805 0.0005
2025-08-15 2025-06-30 13F PROTHENA CORP SHS G72800108 953,256 233,268 32.40 5,786 -35.05 0.0004
2025-05-15 2025-03-31 13F PROTHENA CORP SHS G72800108 719,988 498 0.07 8,910 -10.59 0.0006
2025-05-15 2024-12-31 13F/A-1 PROTHENA CORP SHS G72800108 719,490 203 0.03 9,965 -17.19 0.0007
2025-02-14 2024-12-31 13F PROTHENA CORP SHS G72800108 719,490 203 9,965 0.0007
2025-05-14 2024-09-30 13F/A-2 PROTHENA CORP SHS G72800108 719,287 -91,416 -11.28 12,034 -28.08 0.0009
2025-02-14 2024-09-30 13F/A-1 PROTHENA CORP SHS G72800108 719,287 -91,416 12,034 0.0009
2024-11-14 2024-09-30 13F PROTHENA CORP SHS G72800108 719,287 -91,416 12,034 0.0001
2025-05-14 2024-06-30 13F/A-2 PROTHENA CORP SHS G72800108 810,703 158,235 24.25 16,733 3.53 0.0013
2024-10-17 2024-06-30 13F/A-1 PROTHENA CORP SHS G72800108 810,703 158,235 16,733 0.0013
2024-08-14 2024-06-30 13F PROTHENA CORP SHS G72800108 810,703 158,235 16,733 0.0013
2024-10-17 2024-03-31 13F/A-2 PROTHENA CORP SHS G72800108 652,468 170,208 35.29 16,162 -7.78 0.0013
2024-08-16 2024-03-31 13F/A-1 PROTHENA CORP SHS G72800108 652,468 170,208 16,162 0.0002
2024-05-15 2024-03-31 13F PROTHENA CORP SHS G72800108 652,468 170,208 16,162 0.0013
2024-08-16 2023-12-31 13F/A-1 PROTHENA CORP SHS G72800108 482,260 213,400 79.37 17,525 35.10 0.0015
2024-02-13 2023-12-31 13F PROTHENA CORP SHS G72800108 482,260 213,400 17,525 0.0015
2023-11-15 2023-09-30 13F PROTHENA CORP SHS G72800108 268,860 116,265 76.19 12,972 24.50 0.0013
2023-08-14 2023-06-30 13F PROTHENA CORP SHS G72800108 152,595 -132,312 -46.44 10,419 -24.55 0.0010
2023-05-15 2023-03-31 13F PROTHENA CORP SHS G72800108 284,907 104,504 57.93 13,809 27.05 0.0015
2023-02-14 2022-12-31 13F PROTHENA CORP SHS G72800108 180,403 13,904 8.35 10,869 7.67 0.0012
2022-11-14 2022-09-30 13F PROTHENA CORP SHS G72800108 166,499 -186,083 -52.78 10,095 5.44 0.0014
2022-10-27 2022-06-30 13F/A-1 PROTHENA CORP SHS G72800108 352,582 3,061 0.88 9,574 -25.10 0.0012
2022-08-15 2022-06-30 13F PROTHENA CORP SHS G72800108 352,582 3,061 9,574 0.0012
2022-10-27 2022-03-31 13F/A-1 PROTHENA CORP SHS G72800108 349,521 169,990 94.69 12,782 44.12 0.0017
2022-05-13 2022-03-31 13F PROTHENA CORP SHS G72800108 349,521 169,990 12,782 0.0017
2022-02-14 2021-12-31 13F PROTHENA CORP SHS G72800108 179,531 117,351 188.73 8,869 100.29 0.0011
2021-11-15 2021-09-30 13F PROTHENA CORP SHS G72800108 62,180 17,240 38.36 4,428 91.69 0.0006
2021-08-23 2021-06-30 13F/A-1 PROTHENA CORP SHS G72800108 44,940 30,665 214.82 2,310 543.45 0.0003
2021-08-16 2021-06-30 13F PROTHENA CORP SHS G72800108 44,940 30,665 2,310 0.0001
2021-05-17 2021-03-31 13F PROTHENA CORP SHS G72800108 14,275 -106,757 -88.21 359 -75.29 0.0001
2021-02-16 2020-12-31 13F PROTHENA CORP SHS G72800108 121,032 32,749 37.10 1,453 64.74 0.0002
2020-11-13 2020-09-30 13F PROTHENA CORP SHS G72800108 88,283 -11,990 -11.96 882 -15.84 0.0002
2020-08-14 2020-06-30 13F PROTHENA CORP SHS G72800108 100,273 -6,298 -5.91 1,048 -8.07 0.0002
2020-05-26 2020-03-31 13F/A-1 PROTHENA CORP SHS G72800108 106,571 24,885 30.46 1,140 -11.83 0.0003
2020-05-15 2020-03-31 13F PROTHENA CORP SHS G72800108 106,571 24,885 1,140 87.5758
2020-02-14 2019-12-31 13F PROTHENA CORP SHS G72800108 81,686 -464,910 -85.06 1,293 -69.83 0.0003
2019-11-14 2019-09-30 13F PROTHENA CORP SHS G72800108 546,596 -36,939 -6.33 4,286 -30.51 0.0011
2019-08-14 2019-06-30 13F PROTHENA CORP SHS G72800108 583,535 -97,930 -14.37 6,168 -25.38 0.0016
2019-05-15 2019-03-31 13F PROTHENA CORP SHS G72800108 681,465 581,519 581.83 8,266 703.30 0.0023
2019-02-14 2018-12-31 13F PROTHENA CORP SHS G72800108 99,946 27,366 37.70 1,029 8.54 0.0003
2019-04-23 2018-09-30 13F/A-2 PROTHENA CORP SHS G72800108 72,580 -240,926 -76.85 948 -79.26 0.0002
2018-11-20 2018-09-30 13F/A-1 PROTHENA CORP SHS G72800108 72,580 0 948 0.0002
2018-11-14 2018-09-30 13F PROTHENA CORP SHS G72800108 72,580 -240,926 948
2019-04-23 2018-06-30 13F/A-1 PROTHENA CORP SHS G72800108 313,506 214,004 215.08 4,570 25.10 0.0012
2018-08-14 2018-06-30 13F PROTHENA CORP SHS G72800108 313,506 214,004 4,570
2019-04-23 2018-03-31 13F/A-1 PROTHENA CORP SHS G72800108 99,502 -57,017 -36.43 3,653 -37.74 0.0010
2018-05-14 2018-03-31 13F PROTHENA CORP SHS G72800108 99,502 -57,017 3,653
2019-04-23 2017-12-31 13F/A-1 PROTHENA CORP SHS G72800108 156,519 67,165 75.17 5,867 1.38 0.0016
2018-02-14 2017-12-31 13F PROTHENA CORP SHS G72800108 156,519 67,165 5,867
2017-11-14 2017-09-30 13F PROTHENA CORP SHS G72800108 89,354 20,747 30.24 5,787 55.86 0.0017
2017-08-11 2017-06-30 13F PROTHENA CORP SHS G72800108 68,607 -14,439 -17.39 3,713 -19.86 0.0011
2017-05-22 2017-03-31 13F/A-1 PROTHENA CORP SHS G72800108 83,046 -56,543 -40.51 4,633 -32.53 0.0014
2017-05-12 2017-03-31 13F PROTHENA CORP SHS G72800108 83,046 4,633
2017-02-22 2016-12-31 13F/A-1 PROTHENA CORP SHS G72800108 139,589 102,465 276.01 6,867 208.49 0.0022
2017-02-13 2016-12-31 13F PROTHENA CORP SHS G72800108 139,589 6,867
2016-11-10 2016-09-30 13F PROTHENA CORP SHS G72800108 37,124 -1,426 -3.70 2,226 65.26 0.0008
2016-08-12 2016-06-30 13F PROTHENA CORP SHS G72800108 38,550 18,560 92.85 1,347 63.47 0.0005
2016-05-12 2016-03-31 13F PROTHENA CORP SHS G72800108 19,990 1,243 6.63 824 -35.52 0.0003
2016-02-09 2015-12-31 13F PROTHENA CORP SHS G72800108 18,747 1,830 10.82 1,278 66.41 0.0005
2016-02-08 2015-09-30 13F/A-1 PROTHENA CORP SHS G72800108 16,917 6,560 63.34 768 40.66 0.0003
2015-11-09 2015-09-30 13F PROTHENA CORP SHS G72800108 16,917 768
2015-08-12 2015-06-30 13F PROTHENA CORP SHS G72800108 10,357 -1,591 -13.32 546 20.00 0.0002
2015-05-14 2015-03-31 13F PROTHENA CORP SHS G72800108 11,948 -107,089 -89.96 455 -81.59 0.0002
2015-02-13 2014-12-31 13F PROTHENA CORP SHS G72800108 119,037 105,355 770.03 2,471 715.51 0.0009
2014-12-16 2014-09-30 13F/A-1 PROTHENA CORP SHS G72800108 13,682 -46,171 -77.14 303 -77.54 0.0001
2014-11-14 2014-09-30 13F PROTHENA CORP SHS G72800108 13,682 303
2014-08-12 2014-06-30 13F PROTHENA CORP SHS G72800108 59,853 -148,744 -71.31 1,349 -83.12 0.0023
2014-05-13 2014-03-31 13F PROTHENA CORP SHS G72800108 208,597 201,182 2,713.18 7,991 3,956.35 0.0033
2014-02-13 2013-12-31 13F PROTHENA CORP SHS G72800108 7,415 -56,865 -88.46 197 -84.86 0.0001
2013-11-13 2013-09-30 13F PROTHENA CORPORATION PLC D COM G72800108 64,280 -38,555 -37.49 1,301 -2.11 0.0006
2013-08-08 2013-06-30 13F PROTHENA CORPORATION PLC D COM G72800108 102,835 102,835 1,329 0.0007
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.