PTCT
PTC Therapeutics Inc
68.00$
+0.6%
vs. previous close
Closing price · As of: Sep 17, 2026
Ownership
Ownership Structure
Who owns PTC Therapeutics Inc (PTCT)? This page shows the largest institutions and funds, the ownership structure and the latest insider transactions. 88.3% of the shares are freely tradable; institutional investors hold 117.7%.
Institutional ownership
?Share of the stock held by institutional investors (funds, banks, insurers) according to regulatory filings.
117.7%
Insiders
?Share of the stock held by the executives, founders and major shareholders of the company itself.
7.4%
Float
?Share of stock freely tradable on the market — not locked up in the hands of founders, insiders, or major shareholders.
88.3%
Short % of float
?Shares sold short as a percentage of the freely tradable float — high values signal many bets on falling prices.
16.0%
Shares Outstanding
?Total number of shares issued. Price times share count gives market cap.
84Mio.
Largest Shareholders
Institutions
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| BlackRock Inc | 15.51 | 12,948,717 | +1.3 | 03/31/2026 |
| RTW INVESTMENTS, LLC | 9.28 | 7,746,415 | +0.0 | 03/31/2026 |
| HHG PLC | 8.62 | 7,193,433 | +48.3 | 03/31/2026 |
| Vanguard Portfolio Management, LLC | 5.76 | 4,804,594 | +0.0 | 03/31/2026 |
| State Street Corp | 5.21 | 4,346,519 | +3.3 | 03/31/2026 |
| Wellington Management Company LLP | 4.95 | 4,128,273 | +4.7 | 06/30/2026 |
| Vanguard Capital Management, LLC | 4.40 | 3,676,256 | +0.0 | 03/31/2026 |
| The Toronto-Dominion Bank | 3.63 | 3,025,963 | -26.9 | 03/31/2026 |
Funds
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| iShares Core S&P Small-Cap ETF | 6.06 | 5,056,156 | +0.0 | 08/31/2026 |
| Vanguard MStar Total Stk Mkt Idx Invest | 3.17 | 2,644,725 | +0.3 | 07/31/2026 |
Largest reported positions according to regulatory filings; stake as a percentage of shares outstanding, change versus the previous filing. Source: fundamentals data.
Insider holdings
| Person | Role | Shares | Value | As of | Type |
|---|---|---|---|---|---|
| Schmertzler Michael | Director | 1,316,594 | 89,528,392 $ | Sep 10, 2026 | indirect |
| Klein Matthew B. | CHIEF EXECUTIVE OFFICER | 383,868 | 26,103,024 $ | Aug 4, 2026 | direct |
| Boulding Mark Elliott | EXEC. VP AND CLO | 105,272 | 7,158,496 $ | Aug 17, 2026 | direct |
| Gravier Pierre | CHIEF FINANCIAL OFFICER | 83,986 | 5,711,048 $ | Jul 14, 2026 | direct |
| Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | 60,299 | 4,100,332 $ | Jul 9, 2026 | direct |
| Sollie-Zetlmayer Hege Elisabeth | Director | 52,526 | 3,571,768 $ | Jul 28, 2026 | direct |
| Smith Mary L. | Director | 21,813 | 1,483,284 $ | Jul 9, 2026 | direct |
Holdings as of each person's most recent SEC Form 4 filing — excluding options and RSUs, which are not shares yet. Holdings may have changed between two filings.
Insiders
Insider Transactions
| Date | Person | Role | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| Sep 10, 2026 | Schmertzler Michael | Director | Sell | 10,000 | 67.34 | 673,400 |
| Sep 9, 2026 | Schmertzler Michael | Director | Sell | 572 | 68.67 | 39,279 |
| Sep 9, 2026 | Schmertzler Michael | Director | Sell | 9,428 | 67.79 | 639,124 |
| Aug 27, 2026 | Schmertzler Michael | Director | Sell | 610 | 72.22 | 44,054 |
| Aug 27, 2026 | Schmertzler Michael | Director | Sell | 11,890 | 71.55 | 850,730 |
| Aug 26, 2026 | Schmertzler Michael | Director | Sell | 5,626 | 73.18 | 411,711 |
| Aug 26, 2026 | Schmertzler Michael | Director | Sell | 6,874 | 72.74 | 500,015 |
| Aug 20, 2026 | Schmertzler Michael | Director | Sell | 691 | 72.92 | 50,388 |
| Aug 20, 2026 | Schmertzler Michael | Director | Sell | 2,390 | 71.88 | 171,793 |
| Aug 20, 2026 | Schmertzler Michael | Director | Sell | 9,419 | 70.78 | 666,677 |
| Aug 19, 2026 | Schmertzler Michael | Director | Sell | 7,165 | 73.67 | 527,846 |
| Aug 19, 2026 | Schmertzler Michael | Director | Sell | 5,335 | 72.86 | 388,708 |
| Aug 17, 2026 | Boulding Mark Elliott | EXEC. VP AND CLO | Sell | 969 | 72.90 | 70,640 |
| Aug 17, 2026 | Boulding Mark Elliott | EXEC. VP AND CLO | Sell | 1,844 | 72.39 | 133,487 |
| Aug 17, 2026 | Boulding Mark Elliott | EXEC. VP AND CLO | Other | 2,813 | 25.69 | 72,266 |
| Aug 4, 2026 | Klein Matthew B. | CHIEF EXECUTIVE OFFICER | Sell | 10,292 | 68.57 | 705,722 |
| Jul 28, 2026 | Sollie-Zetlmayer Hege Elisabeth | Director | Other | 2,000 | 0.00 | – |
| Jul 28, 2026 | Sollie-Zetlmayer Hege Elisabeth | Director | Other | 4,000 | 0.00 | – |
| Jul 14, 2026 | Gravier Pierre | CHIEF FINANCIAL OFFICER | Sell | 3,494 | 80.35 | 280,743 |
| Jul 9, 2026 | Smith Mary L. | Director | Sell | 5,834 | 90.00 | 525,060 |
| Jul 9, 2026 | Smith Mary L. | Director | Other | 5,834 | 42.95 | 250,570 |
| Jul 9, 2026 | Smith Mary L. | Director | Sell | 10,000 | 90.00 | 900,000 |
| Jul 9, 2026 | Smith Mary L. | Director | Other | 10,000 | 42.95 | 429,500 |
| Jul 9, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Sell | 2,464 | 90.25 | 222,376 |
| Jul 9, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Other | 2,464 | 46.54 | 114,675 |
| Jul 7, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Sell | 9,288 | 89.44 | 830,719 |
| Jul 7, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Sell | 11,369 | 89.03 | 1,012,182 |
| Jul 7, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Sell | 3,956 | 87.17 | 344,845 |
| Jul 7, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Other | 24,613 | 39.42 | 970,244 |
| Jul 6, 2026 | Boulding Mark Elliott | EXEC. VP AND CLO | Sell | 745 | 86.38 | 64,353 |
| Jul 6, 2026 | Boulding Mark Elliott | EXEC. VP AND CLO | Sell | 645 | 85.84 | 55,367 |
| Jul 6, 2026 | Boulding Mark Elliott | EXEC. VP AND CLO | Sell | 1,036 | 84.41 | 87,449 |
| Jul 6, 2026 | Boulding Mark Elliott | EXEC. VP AND CLO | Sell | 387 | 83.10 | 32,160 |
| Jul 6, 2026 | Boulding Mark Elliott | EXEC. VP AND CLO | Other | 2,813 | 46.54 | 130,917 |
| Jul 6, 2026 | Boulding Mark Elliott | EXEC. VP AND CLO | Sell | 601 | 86.38 | 51,914 |
| Jul 6, 2026 | Boulding Mark Elliott | EXEC. VP AND CLO | Sell | 519 | 85.84 | 44,551 |
| Jul 6, 2026 | Boulding Mark Elliott | EXEC. VP AND CLO | Sell | 833 | 84.41 | 70,314 |
| Jul 6, 2026 | Boulding Mark Elliott | EXEC. VP AND CLO | Sell | 313 | 83.10 | 26,010 |
| Jul 6, 2026 | Boulding Mark Elliott | EXEC. VP AND CLO | Other | 2,266 | 39.42 | 89,326 |
| Jul 6, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Sell | 2,474 | 87.03 | 215,312 |
| Jul 6, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Other | 2,474 | 39.42 | 97,525 |
| Jul 6, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Sell | 10,090 | 86.32 | 870,969 |
| Jul 6, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Sell | 8,786 | 85.35 | 749,885 |
| Jul 6, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Other | 18,876 | 38.10 | 719,176 |
| Jul 6, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Sell | 385 | 86.34 | 33,241 |
| Jul 6, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Sell | 426 | 85.28 | 36,329 |
| Jul 6, 2026 | Almstead Neil Gregory | CHIEF TECHNICAL OPS OFFICER | Other | 811 | 38.10 | 30,899 |
| Apr 21, 2026 | Matthew B Klein | CEO | Sell | 2,850 | 70.91 | 202,094 |
Reportable transactions by officers and major shareholders from SEC Form 4 filings. "Other" includes things like stock grants and option exercises without a buy/sell character. View all insider transactions →
Data as of: September 17, 2026 · Source: fundamental data & SEC filings (annual and quarterly reports, 10-K/10-Q)
Note: pure fact-based analysis, not investment advice and not a solicitation to buy or sell. All figures without guarantee.