[Form 4] Solid Biosciences Inc. Insider Trading Activity

Rhea-AI Filing Summary

Paul Herzich, Chief Technology Officer of Solid Biosciences Inc. (SLDB), reported equity awards granted on 08/14/2025. The filing shows an employee stock option for 100,000 underlying shares with a stated exercise price of $6.17 and an associated record showing 100,000 shares of common stock underlying that option. The filing also reports 50,000 restricted stock units (RSUs), each representing a contingent right to one share, for 50,000 shares of common stock. The RSUs and the option were granted on the same date and the RSUs vest over four years: 50% on the second anniversary of the grant and 25% annually thereafter until the fourth anniversary. The Form 4 was signed by an attorney-in-fact on behalf of Mr. Herzich on 08/18/2025.

Positive

• 100,000-share employee stock option granted with a stated $6.17 exercise price
• 50,000 RSUs granted, each representing a contingent right to one share of common stock
• RSU vesting schedule explicitly disclosed: 50% at second anniversary, then 25% annually thereafter

Negative

• None.

Insights

Compensation Analyst

TL;DR: Routine executive equity grant aligns pay with future stock performance; vesting is backloaded with a 2-year cliff.

The report documents a standard mix of long-term incentives: a 100,000-share option at an indicated exercise price of $6.17 and 50,000 RSUs. The RSU vesting schedule provides a 50% vesting at year two and the remainder over years three and four, which concentrates retention risk through the early period and ties reward to continued service. These award sizes should be viewed relative to company stage and outstanding shares (not provided here). The filing is a clear, single-person Form 4 disclosure with signature by an attorney-in-fact.

Corporate Governance Expert

TL;DR: Disclosure is complete for the grant terms shown; no exercise or sale activity was reported.

The Form 4 discloses a grant transaction occurring on 08/14/2025 and reports the resulting beneficial ownership in both derivative and underlying common shares. The attorney-in-fact signature on 08/18/2025 satisfies filing authentication. The document does not report any exercised options, dispositions, or other compensatory changes beyond the grant, and does not include additional governance or related-party detail.

SEC Form 4

FORM 4

UNITED 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
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

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^*

Herzich Paul

(Last) (First) (Middle)

C/O SOLID BIOSCIENCES INC.

500 RUTHERFORD AVENUE, THIRD FLOOR

(Street)

CHARLESTOWN MA 02129

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Solid Biosciences Inc. [ SLDB ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Technology Officer

3. Date of Earliest Transaction (Month/Day/Year)
08/14/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

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)
			Code	V	Amount	(A) or (D)	Price

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)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Employee Stock Option (Right to Buy)	$6.17	08/14/2025		A		100,000		(1)	08/14/2035	Common Stock	100,000	$0.00	100,000	D
Restricted Stock Units	(2)	08/14/2025		A		50,000		(1)	(1)	Common Stock	50,000	$0.00	50,000	D

Explanation of Responses:

1. The RSUs (as defined in footnote 2) together with this option were granted on August 14, 2025 (the "Grant Date") and vest over four years, with 50% of the original number of shares vesting on the second anniversary of the Grant Date and 25% of the original number of shares annually thereafter until the fourth such anniversary.

2. Each restricted stock unit represents a contingent right to receive one share of the issuer's common stock (the "RSUs").

	/s/ Kimberly Cornwell as attorney-in-fact for Paul Herzich	08/18/2025
	** Signature of Reporting Person	Date
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.
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FAQ

What did Paul Herzich (SLDB) receive on 08/14/2025?

He received an employee stock option for 100,000 shares with a stated exercise price of $6.17 and 50,000 restricted stock units (RSUs) representing rights to common stock.

How do the RSUs awarded to Paul Herzich vest?

The RSUs vest over four years with 50% vesting on the second anniversary of the August 14, 2025 grant date and 25% vesting annually thereafter until the fourth anniversary.

When was the Form 4 signed and by whom?

The Form 4 was signed by Kimberly Cornwell as attorney-in-fact for Paul Herzich on 08/18/2025.

Does the Form 4 report any option exercises or share sales by Paul Herzich?

No. The filing reports only the grant (acquisition) of an option and RSUs; it does not report any exercises or dispositions.

How many shares of common stock are shown as underlying the reported awards?

The filing shows 100,000 shares underlying the option and 50,000 shares underlying the RSUs, totaling 150,000 underlying shares from the reported awards.