Insider Option Exercise and Sales: SNDX 14,400-Share Rule 144 Notice

Rhea-AI Filing Summary

Syndax Pharmaceuticals (SNDX) Form 144 notice reports a proposed sale of 14,400 common shares through Morgan Stanley Smith Barney on NASDAQ, with an aggregate market value of $226,656. The securities were acquired by exercise of stock options on 08/18/2025 and payment was in cash the same day. The filing also discloses two recent Rule 10b5-1 sales by Dennis G. Podlesak in mid-August totaling 38,400 shares for gross proceeds of $570,928.80 ($298,408.32 and $272,520.48). The signee certifies no undisclosed material adverse information and notes any applicable 10b5-1 plan adoption where relevant.

Positive

• Disclosure of option exercise as the acquisition method provides clear provenance for the shares to be sold
• Broker and exchange details (Morgan Stanley Smith Barney; NASDAQ) are provided, supporting transaction transparency
• Prior 10b5-1 sales are disclosed with dates and gross proceeds, showing consistency with planned trading arrangements

Negative

• Insider sales totaling 52,800 shares (14,400 proposed plus 38,400 sold) represent notable insider liquidity that may be viewed negatively by some investors
• Form does not include the 10b5-1 plan adoption date within the remarks section, so timing of the plan relative to sales cannot be confirmed from this content

Insights

Insider Transactions Analyst

TL;DR: Insider exercising options and selling a portion of shares via Rule 144 and 10b5-1, with recent sales generating meaningful cash proceeds.

The notice shows an option exercise on 08/18/2025 followed by a proposed Rule 144 sale of 14,400 shares valued at $226,656, indicating monetization of equity by the holder. Related 10b5-1 executions on 08/14 and 08/15 by Dennis G. Podlesak sold 19,200 shares each for combined gross proceeds of $570,928.80. For investors, these transactions are explicit transfers of insider stock to the market; the filing does not disclose any change in ownership control or new compensation terms beyond the exercised options.

Securities Compliance Expert

TL;DR: Form 144 and referenced 10b5-1 sales appear to document required disclosure for planned insider sales; no regulatory exceptions or violations are stated.

The form lists broker details, nature of acquisition as option exercise, and the signee's representation regarding material non-public information. The presence of prior 10b5-1 sales is disclosed with gross proceeds and dates, which aligns with standard insider disclosure practices. The filing itself contains required elements but does not provide the 10b5-1 plan adoption date within the remarks, so verification of plan timing relative to sales is not available in this text.

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	14400	226656.00	86141862	08/18/2025	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	08/18/2025	Exercise of Stock Options	Issuer			14400	08/18/2025	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 DENNIS G PODLESAK 730 Third Avenue, 9th Floor New York NY 10017	Common	08/15/2025	19200	298408.32
10b5-1 Sales for DENNIS G PODLESAK 730 Third Avenue, 9th Floor New York NY 10017	Common	08/14/2025	19200	272520.48

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

What shares does the SNDX Form 144 propose to sell?

The notice proposes sale of 14,400 common shares on NASDAQ with an aggregate market value of $226,656.

How were the shares acquired that are listed in the Form 144?

The shares were acquired by exercise of stock options on 08/18/2025, with payment in cash.

Who conducted recent insider sales disclosed in this filing?

Two Rule 10b5-1 sales by Dennis G. Podlesak on 08/14/2025 and 08/15/2025 sold 19,200 shares each for gross proceeds of $272,520.48 and $298,408.32 respectively.

Which broker is handling the proposed sale in the Form 144?

The broker listed is Morgan Stanley Smith Barney LLC, Executive Financial Services, New York, NY.

Does the Form 144 state whether the insider knows of any material non-public information?

Yes, the signee represents they do not know any material adverse information about the issuer that has not been publicly disclosed.

Are there indications of a change in ownership or control in this filing?

No. The filing discloses routine insider sales and an option exercise but does not indicate any change in ownership control.