PTC Therapeutics, Inc.
US ˙ NasdaqGS ˙ US69366J2006

SecurityPTCT / PTC Therapeutics, Inc.
InstitutionSei Investments Co
Latest Disclosed Ownership92,089 shares
Latest Disclosed Value $ 6,994,905
Sei Investments Co reports 57.85% increase in ownership of PTCT / PTC Therapeutics, Inc.

On February 13, 2026 - Sei Investments Co filed a 13F-HR form disclosing ownership of 92,089 shares of PTC Therapeutics, Inc. (US:PTCT) valued at $6,995,080 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 13, 2025 disclosing 58,341 shares of PTC Therapeutics, Inc.. This represents a change in shares of 57.85% during the quarter. The current value of the position is $6,324,673 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)
2026-02-13 2025-12-31 13F PTC THERAPEUTICS COM 69366J200 92,089 33,748 57.85 6,995 95.36 0.0069
2025-11-13 2025-09-30 13F PTC THERAPEUTICS COM 69366J200 58,341 -10,727 -15.53 3,580 6.14 0.0039
2025-08-14 2025-06-30 13F PTC THERAPEUTICS COM 69366J200 69,068 57,804 513.17 3,373 487.63 0.0039
2025-05-14 2025-03-31 13F/A-1 PTC THERAPEUTICS COM 69366J200 11,264 5,990 113.58 574 141.18 0.0007
2025-05-13 2025-03-31 13F PTC THERAPEUTICS COM 69366J200 5,274 0 238 0.0003
2025-02-11 2024-12-31 13F PTC THERAPEUTICS COM 69366J200 5,274 5,274 238 0.0003
2023-11-14 2023-09-30 13F PTC THERAPEUTICS COM 69366J200 0 -40,591 -100.00 0 -100.00
2023-08-11 2023-06-30 13F PTC THERAPEUTICS COM 69366J200 40,591 -2,388 -5.56 1,651 -20.71 0.0029
2023-05-12 2023-03-31 13F PTC THERAPEUTICS COM 69366J200 42,979 5,149 13.61 2,082 44.21 0.0039
2023-02-10 2022-12-31 13F PTC THERAPEUTICS COM 69366J200 37,830 -1,131 -2.90 1,444 -26.23 0.0032
2022-11-14 2022-09-30 13F PTC THERAPEUTICS COM 69366J200 38,961 -2,507 -6.05 1,956 17.76 0.0044
2022-08-15 2022-06-30 13F PTC THERAPEUTICS COM 69366J200 41,468 -3,470 -7.72 1,661 -0.95 0.0036
2022-05-13 2022-03-31 13F PTC THERAPEUTICS COM 69366J200 44,938 931 2.12 1,677 -4.34 0.0034
2022-02-14 2021-12-31 13F PTC THERAPEUTICS COM 69366J200 44,007 -209 -0.47 1,753 6.57 0.0033
2021-11-12 2021-09-30 13F PTC THERAPEUTICS COM 69366J200 44,216 -284 -0.64 1,645 -12.55 0.0035
2021-08-06 2021-06-30 13F PTC THERAPEUTICS COM 69366J200 44,500 8,500 23.61 1,881 10.32 0.0042
2021-05-12 2021-03-31 13F PTC THERAPEUTICS COM 69366J200 36,000 -21,937 -37.86 1,705 -51.78 0.0043
2021-02-08 2020-12-31 13F PTC THERAPEUTICS COM 69366J200 57,937 571 1.00 3,536 31.84 0.0091
2020-12-04 2020-09-30 13F/A-1 PTC THERAPEUTICS COM 69366J200 57,366 -29,583 -34.02 2,682 -39.21 0.0078
2020-11-06 2020-09-30 13F PTC THERAPEUTICS COM 69366J200 57,378 -29,571 2,683 6,460.0675
2020-08-17 2020-06-30 13F/A-1 PTC THERAPEUTICS COM 69366J200 86,949 21,862 33.59 4,412 51.93 0.0137
2020-08-11 2020-06-30 13F PTC THERAPEUTICS COM 69366J200 20,512 -44,575 986 2,674.5775
2020-05-14 2020-03-31 13F PTC THERAPEUTICS COM 69366J200 65,087 44,587 217.50 2,904 194.82 0.0107
2020-02-06 2019-12-31 13F PTC THERAPEUTICS COM 69366J200 20,500 20,500 985 0.0029
2019-08-14 2019-06-30 13F PTC THERAPEUTICS COM 69366J200 0 -3,715 -100.00 0 -100.00
2019-05-15 2019-03-31 13F PTC THERAPEUTICS COM 69366J200 3,715 -2,540 -40.61 140 -52.38 0.0005
2019-02-13 2018-12-31 13F PTC THERAPEUTICS COM 69366J200 6,255 0 0.00 294 0.00 0.0010
2018-11-08 2018-09-30 13F PTC THERAPEUTICS COM 69366J200 6,255 5,255 525.50 294 764.71 0.0011
2018-08-03 2018-06-30 13F PTC THERAPEUTICS COM 69366J200 1,000 0 0.00 34 25.93 0.0001
2018-05-11 2018-03-31 13F PTC THERAPEUTICS COM 69366J200 1,000 0 0.00 27 58.82 0.0001
2018-02-08 2017-12-31 13F PTC THERAPEUTICS COM 69366J200 1,000 -115 -10.31 17 -22.73 0.0001
2017-11-06 2017-09-30 13F PTC THERAPEUTICS COM 69366J200 1,115 115 11.50 22 22.22 0.0001
2017-07-31 2017-06-30 13F PTC THERAPEUTICS COM 69366J200 1,000 0 0.00 18 80.00 0.0001
2017-05-05 2017-03-31 13F PTC THERAPEUTICS COM 69366J200 1,000 0 0.00 10 -9.09 0.0000
2017-02-02 2016-12-31 13F PTC THERAPEUTICS COM 69366J200 1,000 -27,869 -96.54 11 -97.28 0.0001
2016-11-04 2016-09-30 13F PTC THERAPEUTICS COM 69366J200 28,869 -212 -0.73 404 98.04 0.0021
2016-08-11 2016-06-30 13F PTC THERAPEUTICS COM 69366J200 29,081 11,741 67.71 204 83.78 0.0012
2016-05-10 2016-03-31 13F/A-1 PTC THERAPEUTICS COM 69366J200 17,340 -23,669 -57.72 111 -91.65 0.0007
2016-02-03 2015-12-31 13F PTC THERAPEUTICS COM 69366J200 41,009 -17,465 -29.87 1,329 -14.86 0.0081
2015-11-02 2015-09-30 13F/A-1 PTC THERAPEUTICS COM 69366J200 58,474 8,106 16.09 1,561 -35.60 0.0143
2015-10-30 2015-09-30 13F DIREXION SHS ETF TR COM 69366J200 58,474 1,563
2015-08-07 2015-06-30 13F/A-1 PTC THERAPEUTICS COM 69366J200 50,368 25,252 100.54 2,424 58.74 0.0219
2015-08-04 2015-06-30 13F PTC THERAPEUTICS COM 69366J200 50,368 25,252 2,424 0.0219
2015-05-14 2015-03-31 13F/A-1 PTC THERAPEUTICS COM 69366J200 25,116 25,116 1,527 0.0133
2015-05-01 2015-03-31 13F PTC THERAPEUTICS COM 69366J200 25,116 1,527
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.