STOCK TITAN

PTC Therapeutics (PTCT) CLO trades options and sells 10K+ shares

Filing Impact
(Neutral)
Filing Sentiment
(Neutral)
Form Type
4

Rhea-AI Filing Summary

PTC Therapeutics executive Mark Elliott Boulding reported an exercise-and-sell transaction in company stock. On June 17, 2026, he exercised stock options to acquire a total of 10,522 shares of Common Stock at an exercise price of $46.54 per share.

On the same date he sold 10,462 shares in open-market transactions at weighted average prices around $78.50–$79.25 per share, executed under a pre-arranged Rule 10b5-1 trading plan adopted on September 10, 2025. Following these transactions, he directly holds 105,272 shares of PTC Therapeutics common stock.

Positive

  • None.

Negative

  • None.
Insider Boulding Mark Elliott
Role EXEC. VP AND CLO
Sold 10,462 shs ($823K)
Type Security Shares Price Value
Exercise Stock Option (Right to Buy) 8,510 $0.00 --
Exercise Stock Option (Right to Buy) 2,012 $0.00 --
Exercise Common Stock 8,510 $46.54 $396K
Sale Common Stock 6,600 $78.50 $518K
Sale Common Stock 1,850 $79.24 $147K
Exercise Common Stock 2,012 $46.54 $94K
Sale Common Stock 1,703 $78.50 $134K
Sale Common Stock 309 $79.25 $24K
Holdings After Transaction: Stock Option (Right to Buy) — 32,950 shares (Direct, null); Common Stock — 113,722 shares (Direct, null)
Footnotes (1)
  1. This transaction was effected pursuant to a written Rule 10b5-1 plan adopted by the Reporting Person on September 10, 2025. This price represents the weighted average price of sale transactions that were executed in multiple trades at prices ranging from $78.00 to $78.99 per share. The Reporting Person hereby undertakes, upon request by the SEC staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price. This price represents the weighted average price of sale transactions that were executed in multiple trades at prices ranging from $79.00 to $79.49 per share. The Reporting Person hereby undertakes, upon request by the SEC staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price. This price represents the weighted average price of sale transactions that were executed in multiple trades at prices ranging from $79.00 to $79.48 per share. The Reporting Person hereby undertakes, upon request by the SEC staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price. This option was granted on January 3, 2025, and vests over four years, with 25% of the shares underlying the option vesting on January 3, 2026, and an additional 6.25% of the original number of shares underlying the option vesting at the end of each successive three-month period thereafter, beginning on April 3, 2026.
Shares sold 10,462 shares Open-market sales on June 17, 2026
Options exercised 10,522 shares Common Stock acquired via option exercise on June 17, 2026
Exercise price $46.54 per share Stock Option (Right to Buy) for Common Stock
Sale price example $79.25 per share One reported weighted average sale price on June 17, 2026
Sale price example $78.50 per share Another reported weighted average sale price on June 17, 2026
Post-transaction holdings 105,272 shares Direct ownership of PTC Therapeutics common stock after trades
Option expiration January 2, 2035 Expiration date of the exercised stock options
10b5-1 plan adoption date September 10, 2025 Date written Rule 10b5-1 trading plan was adopted
Rule 10b5-1 plan regulatory
"This transaction was effected pursuant to a written Rule 10b5-1 plan adopted by the Reporting Person on September 10, 2025."
A Rule 10b5-1 plan is a prearranged, written schedule that lets corporate insiders buy or sell company stock at set times or amounts, even if they later learn material nonpublic information. Think of it like setting an automatic thermostat for trades: it creates a clear record that trades were planned in advance, reducing the risk of insider-trading accusations and helping investors trust that insider transactions are routine rather than based on secret information.
Stock Option (Right to Buy) financial
"security_title: "Stock Option (Right to Buy)" with an exercise price of 46.5400 per share."
weighted average price financial
"This price represents the weighted average price of sale transactions that were executed in multiple trades at prices ranging from $78.00 to $78.99 per share."
Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.
derivative exercise/conversion financial
"transaction_action: "derivative exercise/conversion" and transaction_code_description: "Exercise or conversion of derivative security"."
open-market sale financial
"transaction_action: "open-market sale" and transaction_code "S" for non-derivative Common Stock."
An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.
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Learn about SEC filing dates
SEC Form 4
FORM 4UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940
OMB APPROVAL
OMB Number:3235-0287
Estimated average burden
hours per response:0.5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
X
Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.
1. Name and Address of Reporting Person*
Boulding Mark Elliott

(Last)(First)(Middle)
C/O PTC THERAPEUTICS, INC.
500 WARREN CORPORATE CENTER DRIVE

(Street)
WARREN NEW JERSEY 07059

(City)(State)(Zip)

UNITED STATES

(Country)
2. Issuer Name and Ticker or Trading Symbol
PTC THERAPEUTICS, INC. [ PTCT ]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
Director10% Owner
XOfficer (give title below)Other (specify below)
EXEC. VP AND CLO
2a. Foreign Trading Symbol
3. Date of Earliest Transaction (Month/Day/Year)
06/17/2026
6. Individual or Joint/Group Filing (Check Applicable Line)
XForm filed by One Reporting Person
Form filed by More than One Reporting Person
4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year)2A. Deemed Execution Date, if any (Month/Day/Year)3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeVAmount(A) or (D)Price
Common Stock06/17/2026M(1)8,510A$46.54113,722D
Common Stock06/17/2026S(1)6,600D$78.5(2)107,122D
Common Stock06/17/2026S(1)1,850D$79.24(3)105,272D
Common Stock06/17/2026M(1)2,012A$46.54107,284D
Common Stock06/17/2026S(1)1,703D$78.5(2)105,581D
Common Stock06/17/2026S(1)309D$79.25(4)105,272D
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year)3A. Deemed Execution Date, if any (Month/Day/Year)4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 6. Date Exercisable and Expiration Date (Month/Day/Year)7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeV(A)(D)Date ExercisableExpiration DateTitleAmount or Number of Shares
Stock Option (Right to Buy)$46.5406/17/2026M(1)8,510 (5)01/02/2035Common Stock8,510$032,950D
Stock Option (Right to Buy)$46.5406/17/2026M(1)2,012 (5)01/02/2035Common Stock2,012$030,938D
Explanation of Responses:
1. This transaction was effected pursuant to a written Rule 10b5-1 plan adopted by the Reporting Person on September 10, 2025.
2. This price represents the weighted average price of sale transactions that were executed in multiple trades at prices ranging from $78.00 to $78.99 per share. The Reporting Person hereby undertakes, upon request by the SEC staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price.
3. This price represents the weighted average price of sale transactions that were executed in multiple trades at prices ranging from $79.00 to $79.49 per share. The Reporting Person hereby undertakes, upon request by the SEC staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price.
4. This price represents the weighted average price of sale transactions that were executed in multiple trades at prices ranging from $79.00 to $79.48 per share. The Reporting Person hereby undertakes, upon request by the SEC staff, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price.
5. This option was granted on January 3, 2025, and vests over four years, with 25% of the shares underlying the option vesting on January 3, 2026, and an additional 6.25% of the original number of shares underlying the option vesting at the end of each successive three-month period thereafter, beginning on April 3, 2026.
/s/ Avraham S. Adler, Attorney-in-Fact06/22/2026
** Signature of Reporting PersonDate
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transaction did PTC Therapeutics (PTCT) report for Mark Elliott Boulding?

PTC Therapeutics reported that executive Mark Elliott Boulding exercised stock options and sold shares. He acquired 10,522 common shares through option exercises, then sold 10,462 shares in open-market trades while retaining 105,272 shares directly after the transactions.

How many PTC Therapeutics (PTCT) shares did Mark Elliott Boulding sell and at what prices?

Mark Elliott Boulding sold 10,462 PTC Therapeutics common shares. The reported weighted average sale prices ranged from about $78.50 to $79.25 per share, reflecting multiple open-market trades executed on June 17, 2026.

How many PTC Therapeutics (PTCT) shares does Mark Elliott Boulding own after this Form 4?

After the reported transactions, Mark Elliott Boulding directly owns 105,272 PTC Therapeutics common shares. This figure reflects both his June 17, 2026 stock option exercises and the same-day open-market sales disclosed in the Form 4.

Were Mark Elliott Boulding’s PTC Therapeutics (PTCT) share sales part of a Rule 10b5-1 plan?

Yes. The filing states the sales were executed under a written Rule 10b5-1 trading plan. That plan was adopted on September 10, 2025, indicating the transactions were pre-arranged rather than discretionary market-timing decisions.

What stock options did Mark Elliott Boulding exercise for PTC Therapeutics (PTCT)?

He exercised options covering 10,522 shares of PTC Therapeutics common stock at a $46.54 exercise price. The options were granted on January 3, 2025 and are scheduled to vest over four years, with an expiration date of January 2, 2035.

What is Mark Elliott Boulding’s role at PTC Therapeutics (PTCT) in this Form 4?

The Form 4 identifies Mark Elliott Boulding as an officer of PTC Therapeutics, serving as Executive Vice President and Chief Legal Officer. The reported transactions therefore reflect trading activity by a senior company executive.