[Form 4] Rhythm Pharmaceuticals, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Rhythm Pharmaceuticals (RYTM) – insider Form 4 filing

Chief Scientific Officer Alastair Garfield settled 4,445 restricted stock units on 1-Jul-2025, receiving an equal number of common shares. On 2-Jul-2025 he sold 1,319 of those shares in two trades at prices of $64.81 and $64.60 under a pre-arranged Rule 10b5-1 plan adopted 25-Jun-2024, with the stated purpose of covering withholding taxes. After the transactions he retains 3,126 directly held shares and 13,333 unvested RSUs that vest 25 % annually through 1-Jul-2028, subject to continued employment. No other equity instruments were created or disposed of. Given the modest size of the sale relative to Rhythm’s share count and its tax-related rationale, the event is viewed as routine compensation management with limited signaling value for investors.

Insights

Securities Analyst

TL;DR: Routine RSU vesting; minor tax-related sale; neutral signal for RYTM shareholders.

The CSO converted 4,445 RSUs and sold 1,319 shares (~$85k gross proceeds) strictly to satisfy tax obligations. His remaining equity exposure—3,126 shares plus 13,333 unvested RSUs—maintains alignment with shareholders. Volume is immaterial against Rhythm’s ~60 million shares outstanding and does not suggest strategic de-risking. I classify the filing as informationally neutral and not price-moving.

Corporate Governance Expert

TL;DR: Pre-planned 10b5-1 sale limits governance concerns; impact minimal.

The transaction followed a disclosed 10b5-1 plan, reinforcing compliance with updated SEC affirmative-defense rules. No red flags arise: sale size is small, purpose is tax coverage, and long-term incentives remain intact. The event demonstrates proper governance practices and transparent insider trading controls, but it carries negligible financial impact.

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
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^*

Garfield Alastair

(Last) (First) (Middle)

222 BERKELEY STREET, 12TH FLOOR

(Street)

BOSTON MA 02116

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
RHYTHM PHARMACEUTICALS, INC. [ RYTM ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
07/01/2025

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
Common Stock	07/01/2025		M		4,445	A	(1)	4,445	D
Common Stock	07/02/2025		S(2)		1,313	D	$64.81	3,132	D
Common Stock	07/02/2025		S(2)		6	D	$64.6	3,126	D

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
Restricted Stock Units	(1)	07/01/2025		M			4,445	(3)	(3)	Common Stock	4,445	$0	13,333	D

Explanation of Responses:

1. Each restricted stock unit represents a contingent right to receive one share of Issuer common stock.

2. The sale reported in this Form 4 was effected pursuant to Rule 10b5-1 instruction adopted on June 25, 2024 solely with the intent to cover withholding taxes in connection with the vesting of certain previously reported restricted stock units.

3. The restricted stock units vest as to 25% of the total restricted stock units on each of the first four anniversaries of July 1, 2024, subject to the Reporting Person's continued service on each such vesting date. The restricted stock units have no expiration date.

	/s/ Stephen Vander Stoep, attorney-in-fact for Alastair Garfield	07/03/2025
	** 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.
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.

FAQ

How many Rhythm Pharmaceuticals (RYTM) shares did the CSO sell?

Alastair Garfield sold 1,319 common shares on 2-Jul-2025 at an average price of about $64.8 per share.

Was the insider sale pre-planned under a Rule 10b5-1 trading plan?

Yes. The filing states the sale was executed under a Rule 10b5-1 plan adopted on 25-Jun-2024.

What was the purpose of the share sale disclosed in the Form 4?

The sale was solely to cover withholding taxes triggered by the RSU vesting event.

How many Rhythm Pharmaceuticals shares and RSUs does the CSO still hold?

Post-transaction, Garfield owns 3,126 common shares directly and 13,333 unvested RSUs.

When will the remaining RSUs vest?

The RSUs vest in 25 % annual installments on each anniversary of 1-Jul-2024 through 2028, subject to continued service.