PTC Therapeutics CLO Mark Boulding Exercises Options, Sells Shares

What Happened
Mark Elliott Boulding, Executive Vice President and Chief Legal Officer of PTC Therapeutics (PTCT), exercised options to acquire 2,813 common shares at $25.69 per share (cost $72,266) on August 17, 2026, and sold those 2,813 shares the same day in two open‑market transactions for total gross proceeds of $204,127 (1,844 shares at a weighted $72.39 for $133,487; 969 shares at a weighted $72.90 for $70,640). The Form 4 shows the option exercise/conversion entries and the matching sales.

Key Details

• Transaction date: August 17, 2026 (filed Aug 19, 2026 — within the typical 2 business‑day Form 4 window).
• Exercise: 2,813 shares @ $25.69 = $72,266.
• Sales: 1,844 shares @ weighted $72.39 = $133,487 (prices ranged $71.72–$72.67 per F2); 969 shares @ weighted $72.90 = $70,640 (prices ranged $72.73–$73.02 per F3). Total gross sales ≈ $204,127.
• Shares owned after transaction: Not stated in this filing.
• Notable footnotes: F1 — sales effected under a written Rule 10b5‑1 trading plan adopted Sept 10, 2025; F4 — option was granted Feb 15, 2024 with multi‑year vesting schedule; F2/F3 — weighted average sale prices represent multiple trades (ranges provided).
• No indication in the filing that the report was late.

Context
This was an option exercise followed by sales of the same number of shares, a common pattern used to cover option exercise cost and related tax withholding (sometimes referred to as a cashless exercise). Because the sales were executed under a pre‑arranged 10b5‑1 plan, they were scheduled in advance; the filing itself is factual and does not state the insider’s motivation. Purchases (buys) generally carry more weight for signaling, while routine exercises followed by sales are often administrative.