[144] Rhythm Pharmaceuticals, Inc. SEC Filing

Rhea-AI Filing Summary

OneStream, Inc. (OS) Form 4 filing: Director Jonathan D. Mariner sold 6,630 Class A common shares on 07/07/2025 at a weighted-average price of $26.59 under a Rule 10b5-1 trading plan adopted on 02/28/2025. After the sale, Mariner still beneficially owns 40,280 shares, which include unvested restricted stock units. No derivative transactions were reported.

The transaction reduces Mariner’s direct holdings by roughly 14% but maintains a sizable position, suggesting portfolio rebalancing rather than a full exit. The use of a pre-arranged plan limits the signaling effect because it indicates the sale was scheduled in advance and not driven by new, undisclosed information.

Positive

• Sale executed under a Rule 10b5-1 plan, indicating pre-planned disposition and reducing concerns about opportunistic trading.

Negative

• Director reduced direct ownership by 6,630 shares (≈14%), which can be interpreted as a modestly bearish insider signal.

Insights

Securities Analyst

TL;DR: Director sells 6,630 shares (~$176k) via 10b5-1; modestly negative sentiment.

The filing shows a single, routine sale representing about 14% of the director’s stake, leaving over 40k shares outstanding. Because the transaction occurred under a 10b5-1 plan, the informational value is muted; however, insider selling—particularly by a board member—generally skews slightly bearish for near-term sentiment. The remaining stake and continued board role temper concerns. Overall impact on valuation is minimal, but traders may view the activity as a short-term supply overhang.

Form 144 Filer Information	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 144 NOTICE OF PROPOSED SALE OF SECURITIES PURSUANT TO RULE 144 UNDER THE SECURITIES ACT OF 1933
FORM 144

144: Filer Information

Filer CIK
Filer CCC
Is this a LIVE or TEST Filing?	LIVE TEST
Submission Contact Information
Name
Phone
E-Mail Address

144: Issuer Information

Name of Issuer

SEC File Number

Address of Issuer

Phone

Name of Person for Whose Account the Securities are To Be Sold

See the definition of "person" in paragraph (a) of Rule 144. Information is to be given not only as to the person for whose account the securities are to be sold but also as to all other persons included in that definition. In addition, information shall be given as to sales by all persons whose sales are required by paragraph (e) of Rule 144 to be aggregated with sales for the account of the person filing this notice.

Relationship to Issuer

144: Securities Information

Title of the Class of Securities To Be Sold	Name and Address of the Broker	Number of Shares or Other Units To Be Sold	Aggregate Market Value	Number of Shares or Other Units Outstanding	Approximate Date of Sale	Name the Securities Exchange
Common	Morgan Stanley Smith Barney LLC Executive Financial Services 1 New York Plaza 8th Floor New York NY 10004	15572	1014360.08	63621472	07/09/2025	NASDAQ

Furnish the following information with respect to the acquisition of the securities to be sold and with respect to the payment of all or any part of the purchase price or other consideration therefor:

144: Securities To Be Sold

Title of the Class	Date you Acquired	Nature of Acquisition Transaction	Name of Person from Whom Acquired	Is this a Gift?	Date Donor Acquired	Amount of Securities Acquired	Date of Payment	Nature of Payment *
Common	07/09/2025	Exercise of Stock Options	Issuer			15572	07/09/2025	Cash

* If the securities were purchased and full payment therefor was not made in cash at the time of purchase, explain in the table or in a note thereto the nature of the consideration given. If the consideration consisted of any note or other obligation, or if payment was made in installments describe the arrangement and state when the note or other obligation was discharged in full or the last installment paid.

Furnish the following information as to all securities of the issuer sold during the past 3 months by the person for whose account the securities are to be sold.

144: Securities Sold During The Past 3 Months

Name and Address of Seller	Title of Securities Sold	Date of Sale	Amount of Securities Sold	Gross Proceeds
10b5-1 Sales for PAMELA CRAMER 222 Berkeley Street, 12th Floor BOSTON MA 02116	Common	06/06/2025	7031	478434.94
10b5-1 Sales for PAMELA CRAMER 222 Berkeley Street, 12th Floor BOSTON MA 02116	Common	04/29/2025	7031	457663.26

144: Remarks and Signature

Remarks

Date of Notice

Date of Plan Adoption or Giving of Instruction, If Relying on Rule 10b5-1

ATTENTION:

The person for whose account the securities to which this notice relates are to be sold hereby represents by signing this notice that he does not know any material adverse information in regard to the current and prospective operations of the Issuer of the securities to be sold which has not been publicly disclosed. If such person has adopted a written trading plan or given trading instructions to satisfy Rule 10b5-1 under the Exchange Act, by signing the form and indicating the date that the plan was adopted or the instruction given, that person makes such representation as of the plan adoption or instruction date.

Signature

ATTENTION: Intentional misstatements or omission of facts constitute Federal Criminal Violations (See 18 U.S.C. 1001)

FAQ

How many OneStream (OS) shares did Director Jonathan D. Mariner sell?

He sold 6,630 Class A common shares on 07/07/2025.

What price did the OS shares sell for?

The weighted-average sale price was $26.59 per share, within a range of $26.35–$26.76.

Does Mariner still hold OneStream stock after the sale?

Yes. He beneficially owns 40,280 shares, including unvested restricted stock units.

Was the sale part of a Rule 10b5-1 trading plan?

Yes. The plan was adopted on 02/28/2025, indicating the sale was pre-arranged.

Is any derivative security activity disclosed in this Form 4?

No. The filing reports no derivative transactions for the period.