Hunter C. Smith - 12 Aug 2025 Form 4 Insider Report for RHYTHM PHARMACEUTICALS, INC. (RYTM)

Signature
/s/ Stephen Vander Stoep, attorney-in-fact for Hunter C. Smith
Issuer symbol
RYTM
Transactions as of
12 Aug 2025
Net transactions value
-$2,511,378
Form type
4
Filing time
14 Aug 2025, 18:48:32 UTC
Previous filing
11 Jul 2025
Next filing
03 Feb 2026

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Smith Hunter C Chief Financial Officer C/O RHYTHM PHARMACEUTICALS, INC., 222 BERKELEY STREET, 12TH FLOOR, BOSTON /s/ Stephen Vander Stoep, attorney-in-fact for Hunter C. Smith 14 Aug 2025 0001636385

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction RYTM Common Stock Options Exercise $169,324 +24,611 +21% $6.88 141,526 12 Aug 2025 Direct
transaction RYTM Common Stock Sale $2,370,832 -24,611 -17% $96.33 116,915 12 Aug 2025 Direct F1, F2
transaction RYTM Common Stock Options Exercise $23,922 +3,477 +3% $6.88 120,392 13 Aug 2025 Direct
transaction RYTM Common Stock Sale $333,792 -3,477 -2.9% $96.00 116,915 13 Aug 2025 Direct F1

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction RYTM Stock Options (Right to Buy) Options Exercise $0 -24,611 -88% $0.000000 3,477 12 Aug 2025 Common Stock 24,611 $6.88 Direct F3
transaction RYTM Stock Options (Right to Buy) Options Exercise $0 -3,477 -100% $0.000000 0 13 Aug 2025 Common Stock 3,477 $6.88 Direct F3
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Buy Plan / Sale Plan: These are also open market purchases/sales of shares, but in this case the transaction is part of a trading plan. Rule 10b5-1 allows insiders to setup a trading plan to buy/sell stocks over a certain period of time. Since the purchases/sales are predetermined, this protects the insiders from violating insider trading law.

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).

Explanation of Responses:

Id Content
F1 The sale reported in the Form 4 was effected pursuant to a Rule 10b5-1 plan adopted by the Reporting Person on February 28, 2025.
F2 The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $96.00 to $96.63 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.
F3 The stock option is fully vested.