STOCK TITAN

PTC Therapeutics (PTCT) CLO exercises options and sells 2,812 shares under 10b5-1 plan

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

Rhea-AI Filing Summary

PTC Therapeutics executive Mark Elliott Boulding, Executive VP and CLO, exercised stock options for 2,812 shares of Common Stock at $25.69 per share and, on the same date, sold 2,812 shares in open-market transactions at weighted average prices of $72.67 and $72.08. These trades were made under a pre-arranged Rule 10b5-1 plan. Following the transactions, he directly holds 105,212 Common Stock shares and 19,689 stock options.

Positive

  • None.

Negative

  • None.
Insider Boulding Mark Elliott
Role EXEC. VP AND CLO
Sold 2,812 shs ($203K)
Type Security Shares Price Value
Exercise Stock Option (Right to Buy) 2,812 $0.00 --
Exercise Common Stock 2,812 $25.69 $72K
Sale Common Stock 2,356 $72.08 $170K
Sale Common Stock 456 $72.67 $33K
Holdings After Transaction: Stock Option (Right to Buy) — 19,689 shares (Direct, null); Common Stock — 108,024 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 $71.41 to $72.29 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 $72.41 to $72.99 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 option was granted on February 15, 2024, and vests over four years, with 25% of the shares underlying the option vesting on February 15, 2025, 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 May 15, 2025.
Shares sold 2,812 shares Open-market sales of Common Stock on May 15, 2026
Sale prices $72.67 and $72.08 per share Weighted average sale prices for two sale blocks
Option exercise price $25.69 per share Conversion price for exercised stock option
Common shares after trades 105,212 shares Direct Common Stock holdings following transactions
Options remaining 19,689 options Stock options outstanding after the reported exercise
Rule 10b5-1 plan adoption date September 10, 2025 Date trading plan governing sales was adopted
Option grant date February 15, 2024 Grant date of the exercised stock option
Option expiration February 14, 2034 Expiration date of the underlying stock option grant
Rule 10b5-1 plan regulatory
"This transaction was effected pursuant to a written Rule 10b5-1 plan adopted by the Reporting Person"
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.
weighted average price financial
"This price represents the weighted average price of sale transactions that were executed in multiple trades"
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.
Stock Option (Right to Buy) financial
"security_title: Stock Option (Right to Buy)"
vests over four years financial
"This option was granted on February 15, 2024, and vests over four years"
A grant that "vests over four years" is a promise that ownership of awarded company shares or options becomes permanent in small portions over a four-year period instead of all at once. Think of it like earning a four-year subscription one month at a time: the recipient gains the right to a bit more stock as time passes, which matters to investors because it affects when employees can sell shares, how quickly ownership shifts, and the timing of potential dilution or insider selling.
Common Stock financial
"security_title: Common Stock"
Common stock represents ownership shares in a company, giving investors a stake in its success and a say in important decisions through voting rights. It is the most common type of stock traded on markets and can provide income through dividends, as well as potential for value growth. For investors, holding common stock means sharing in the company’s profits and risks.
See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google
Add on Google
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)
05/15/2026
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 Stock05/15/2026M(1)2,812A$25.69108,024D
Common Stock05/15/2026S(1)2,356D$72.08(2)105,668D
Common Stock05/15/2026S(1)456D$72.67(3)105,212D
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)$25.6905/15/2026M(1)2,812 (4)02/14/2034Common Stock2,812$019,689D
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 $71.41 to $72.29 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 $72.41 to $72.99 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.
4. This option was granted on February 15, 2024, and vests over four years, with 25% of the shares underlying the option vesting on February 15, 2025, 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 May 15, 2025.
/s/ Avraham S. Adler, Attorney-in-Fact05/19/2026
** 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 transactions did PTCT executive Mark Elliott Boulding report?

Mark Elliott Boulding reported exercising options for 2,812 PTCT shares and selling 2,812 shares in open-market trades. The activity combined an option exercise at a lower strike price with same-day sales at higher market prices.

At what prices did Mark Elliott Boulding sell PTC Therapeutics (PTCT) shares?

He sold PTCT shares at weighted average prices of $72.67 and $72.08 per share. Each average reflects multiple trades within narrow price ranges, as disclosed, with detailed breakdowns available upon request to the company or regulators.

What stock option exercise did the PTCT Form 4 disclose for Mark Elliott Boulding?

The Form 4 shows Boulding exercised a stock option for 2,812 PTCT Common Stock shares at a conversion price of $25.69 per share. This option was part of a grant made on February 15, 2024, that vests quarterly over four years.

How many PTC Therapeutics (PTCT) shares does Mark Elliott Boulding hold after these transactions?

After the reported trades, Boulding directly holds 105,212 PTCT Common Stock shares. He also retains 19,689 stock options, giving him continued equity exposure beyond the shares sold in these open-market transactions.

Were Mark Elliott Boulding’s PTCT share sales under a Rule 10b5-1 trading plan?

Yes. The filing states the sales were executed under a written Rule 10b5-1 plan adopted on September 10, 2025. Such pre-arranged plans automate trades and can reduce the significance of transaction timing as a discretionary signal.

What are the vesting terms of Mark Elliott Boulding’s PTCT stock option grant?

The option was granted on February 15, 2024, with 25% vesting on February 15, 2025. An additional 6.25% of the original option shares vest at the end of each three-month period starting May 15, 2025, over four years.