PTC Therapeutics, Inc.
US ˙ NasdaqGS ˙ US69366J2006

SecurityPTCT / PTC Therapeutics, Inc.
InstitutionMorgan Stanley
Latest Disclosed Ownership674,134 shares
Latest Disclosed Value $ 45,928,802
Morgan Stanley reports 25.53% decrease in ownership of PTCT / PTC Therapeutics, Inc.

On May 15, 2026 - Morgan Stanley filed a 13F-HR form disclosing ownership of 674,134 shares of PTC Therapeutics, Inc. (US:PTCT) valued at $45,928,749 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on May 27, 2026 disclosing 905,192 shares of PTC Therapeutics, Inc.. This represents a change in shares of -25.53% during the quarter. The current value of the position is $47,843,290 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 PTC THERAPEUTICS COM 69366J200 674,134 -231,058 -25.53 45,929 -33.20 0.0028
2026-05-27 2025-12-31 13F/A-1 PTC THERAPEUTICS COM 69366J200 905,192 485,775 115.82 68,758 167.14 0.0041
2026-02-13 2025-12-31 13F PTC THERAPEUTICS COM 69366J200 905,192 485,775 68,758 0.0041
2026-05-27 2025-09-30 13F/A-1 PTC THERAPEUTICS COM 69366J200 419,417 -743,922 -63.95 25,740 -54.70 0.0016
2025-11-14 2025-09-30 13F PTC THERAPEUTICS COM 69366J200 419,417 -743,922 25,740 0.0016
2025-08-15 2025-06-30 13F PTC THERAPEUTICS COM 69366J200 1,163,339 213,905 22.53 56,818 17.43 0.0037
2025-05-15 2025-03-31 13F PTC THERAPEUTICS COM 69366J200 949,434 -124,383 -11.58 48,383 -0.18 0.0035
2025-05-15 2024-12-31 13F/A-1 PTC THERAPEUTICS COM 69366J200 1,073,817 -84,237 -7.27 48,472 12.82 0.0034
2025-02-14 2024-12-31 13F PTC THERAPEUTICS COM 69366J200 1,073,817 -84,237 48,472 0.0034
2025-05-14 2024-09-30 13F/A-2 PTC THERAPEUTICS COM 69366J200 1,158,054 -358,703 -23.65 42,964 -7.37 0.0031
2025-02-14 2024-09-30 13F/A-1 PTC THERAPEUTICS COM 69366J200 1,158,054 -358,703 42,964 0.0031
2024-11-14 2024-09-30 13F PTC THERAPEUTICS COM 69366J200 1,158,054 -358,703 42,964 0.0004
2025-05-14 2024-06-30 13F/A-2 PTC THERAPEUTICS COM 69366J200 1,516,757 -546,284 -26.48 46,382 -22.71 0.0036
2024-10-17 2024-06-30 13F/A-1 PTC THERAPEUTICS COM 69366J200 1,516,757 -546,284 46,382 0.0036
2024-08-14 2024-06-30 13F PTC THERAPEUTICS COM 69366J200 1,516,757 -546,284 46,382 0.0036
2024-10-17 2024-03-31 13F/A-2 PTC THERAPEUTICS COM 69366J200 2,063,041 816,782 65.54 60,014 74.73 0.0048
2024-08-16 2024-03-31 13F/A-1 PTC THERAPEUTICS COM 69366J200 2,063,041 816,782 60,014 0.0006
2024-05-15 2024-03-31 13F PTC THERAPEUTICS COM 69366J200 2,063,041 816,782 60,014 0.0048
2024-08-16 2023-12-31 13F/A-1 PTC THERAPEUTICS COM 69366J200 1,246,259 810,519 186.01 34,347 251.76 0.0030
2024-02-13 2023-12-31 13F PTC THERAPEUTICS COM 69366J200 1,246,259 810,519 34,347 0.0030
2023-11-15 2023-09-30 13F PTC THERAPEUTICS COM 69366J200 435,740 54,664 14.34 9,765 -37.00 0.0010
2023-08-14 2023-06-30 13F PTC THERAPEUTICS COM 69366J200 381,076 155,186 68.70 15,498 41.64 0.0015
2023-05-15 2023-03-31 13F PTC THERAPEUTICS COM 69366J200 225,890 -71,775 -24.11 10,942 -3.69 0.0012
2023-02-14 2022-12-31 13F PTC THERAPEUTICS COM 69366J200 297,665 13,416 4.72 11,362 -20.39 0.0013
2022-11-14 2022-09-30 13F PTC THERAPEUTICS COM 69366J200 284,249 -140,138 -33.02 14,270 -16.06 0.0019
2022-10-27 2022-06-30 13F/A-1 PTC THERAPEUTICS COM 69366J200 424,387 80,853 23.54 17,001 32.64 0.0022
2022-08-15 2022-06-30 13F PTC THERAPEUTICS COM 69366J200 424,387 80,853 17,001 0.0022
2022-10-27 2022-03-31 13F/A-1 PTC THERAPEUTICS COM 69366J200 343,534 127,819 59.25 12,817 49.17 0.0017
2022-05-13 2022-03-31 13F PTC THERAPEUTICS COM 69366J200 343,534 127,819 12,817 0.0017
2022-02-14 2021-12-31 13F PTC THERAPEUTICS COM 69366J200 215,715 173,765 414.22 8,592 450.42 0.0011
2021-11-15 2021-09-30 13F PTC THERAPEUTICS COM 69366J200 41,950 -137,531 -76.63 1,561 -79.43 0.0002
2021-08-23 2021-06-30 13F/A-1 PTC THERAPEUTICS COM 69366J200 179,481 160,778 859.64 7,588 757.40 0.0010
2021-08-16 2021-06-30 13F PTC THERAPEUTICS COM 69366J200 179,481 160,778 7,588 0.0002
2021-05-17 2021-03-31 13F PTC THERAPEUTICS COM 69366J200 18,703 -33,173 -63.95 885 -72.04 0.0001
2021-02-16 2020-12-31 13F PTC THERAPEUTICS COM 69366J200 51,876 32,022 161.29 3,165 241.42 0.0005
2020-11-13 2020-09-30 13F PTC THERAPEUTICS COM 69366J200 19,854 -8,484 -29.94 927 -35.54 0.0002
2020-08-14 2020-06-30 13F PTC THERAPEUTICS COM 69366J200 28,338 -57,534 -67.00 1,438 -62.45 0.0003
2020-05-26 2020-03-31 13F/A-1 PTC THERAPEUTICS COM 69366J200 85,872 -191,059 -68.99 3,830 -71.20 0.0010
2020-05-15 2020-03-31 13F PTC THERAPEUTICS COM 69366J200 85,872 -191,059 3,830 294.2238
2020-02-14 2019-12-31 13F PTC THERAPEUTICS COM 69366J200 276,931 216,665 359.51 13,300 552.60 0.0031
2019-11-14 2019-09-30 13F PTC THERAPEUTICS COM 69366J200 60,266 20,336 50.93 2,038 13.41 0.0005
2019-08-14 2019-06-30 13F PTC THERAPEUTICS COM 69366J200 39,930 14,919 59.65 1,797 90.76 0.0005
2019-05-15 2019-03-31 13F PTC THERAPEUTICS COM 69366J200 25,011 -74,126 -74.77 942 -72.31 0.0003
2019-02-14 2018-12-31 13F PTC THERAPEUTICS COM 69366J200 99,137 -72,309 -42.18 3,402 -57.78 0.0010
2019-04-23 2018-09-30 13F/A-2 PTC THERAPEUTICS COM 69366J200 171,446 -403,743 -70.19 8,058 -58.47 0.0020
2018-11-20 2018-09-30 13F/A-1 PTC THERAPEUTICS COM 69366J200 171,446 0 8,058 0.0020
2018-11-14 2018-09-30 13F PTC THERAPEUTICS COM 69366J200 171,446 -403,743 8,058
2019-04-23 2018-06-30 13F/A-1 PTC THERAPEUTICS COM 69366J200 575,189 -36,533 -5.97 19,401 17.21 0.0052
2018-08-14 2018-06-30 13F PTC THERAPEUTICS COM 69366J200 575,189 -36,533 19,401
2019-04-23 2018-03-31 13F/A-1 PTC THERAPEUTICS COM 69366J200 611,722 478,675 359.78 16,553 645.97 0.0046
2018-05-14 2018-03-31 13F PTC THERAPEUTICS COM 69366J200 611,722 478,675 16,553
2019-04-23 2017-12-31 13F/A-1 PTC THERAPEUTICS COM 69366J200 133,047 29,357 28.31 2,219 6.94 0.0006
2018-02-14 2017-12-31 13F PTC THERAPEUTICS COM 69366J200 133,047 29,357 2,219
2017-11-14 2017-09-30 13F PTC THERAPEUTICS COM 69366J200 103,690 -473,167 -82.03 2,075 -80.38 0.0006
2017-08-11 2017-06-30 13F PTC THERAPEUTICS COM 69366J200 576,857 501,534 665.84 10,574 1,325.07 0.0032
2017-05-22 2017-03-31 13F/A-1 PTC THERAPEUTICS COM 69366J200 75,323 -219,780 -74.48 742 -76.95 0.0002
2017-05-12 2017-03-31 13F PTC THERAPEUTICS COM 69366J200 75,323 742
2017-02-22 2016-12-31 13F/A-1 PTC THERAPEUTICS COM 69366J200 295,103 263,510 834.08 3,219 628.28 0.0011
2017-02-13 2016-12-31 13F PTC THERAPEUTICS COM 69366J200 295,103 3,219
2016-11-10 2016-09-30 13F PTC THERAPEUTICS COM 69366J200 31,593 10,085 46.89 442 192.72 0.0002
2016-08-12 2016-06-30 13F PTC THERAPEUTICS COM 69366J200 21,508 10,419 93.96 151 109.72 0.0001
2016-05-12 2016-03-31 13F PTC THERAPEUTICS COM 69366J200 11,089 5,578 101.22 72 -59.55 0.0000
2016-02-09 2015-12-31 13F PTC THERAPEUTICS COM 69366J200 5,511 -59,862 -91.57 178 -89.81 0.0001
2016-02-08 2015-09-30 13F/A-1 PTC THERAPEUTICS COM 69366J200 65,373 35,027 115.43 1,746 19.51 0.0006
2015-11-09 2015-09-30 13F PTC THERAPEUTICS COM 69366J200 65,373 1,746
2015-08-12 2015-06-30 13F PTC THERAPEUTICS COM 69366J200 30,346 16,116 113.25 1,461 68.71 0.0005
2015-05-14 2015-03-31 13F PTC THERAPEUTICS COM 69366J200 14,230 -2,899 -16.92 866 -2.37 0.0003
2015-02-13 2014-12-31 13F PTC THERAPEUTICS COM 69366J200 17,129 5,791 51.08 887 77.76 0.0003
2014-12-16 2014-09-30 13F/A-1 PTC THERAPEUTICS COM 69366J200 11,338 -1,316 -10.40 499 50.76 0.0002
2014-11-14 2014-09-30 13F PTC THERAPEUTICS COM 69366J200 11,338 499
2014-05-13 2014-03-31 13F PTC THERAPEUTICS COM 69366J200 12,654 5,960 89.03 331 190.35 0.0001
2014-02-13 2013-12-31 13F PTC THERAPEUTICS COM 69366J200 6,694 6,694 114 0.0000
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.