Michael A. Metzger - 08 Jul 2026 Form 4 Insider Report for Syndax Pharmaceuticals Inc (SNDX)

Reporting relationship: Chief Executive Officer, Director
Issuer ticker: SNDX
Reported as of: 08 Jul 2026
Net transaction value: -$784,776
SEC form: 4
Accepted by SEC: 09 Jul 2026, 16:54:03 UTC
Prior SEC filing: 02 Jun 2026
Source filing: View source filing
Reporting owner signature: /s/ Michael A. Metzger

Key filing fact

Michael A. Metzger filed Form 4 for Syndax Pharmaceuticals Inc (SNDX) on 09 Jul 2026.

Key facts

This page summarizes Michael A. Metzger's Form 4 filing for Syndax Pharmaceuticals Inc (SNDX).
3 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 09 Jul 2026, 16:54.

Change

Previous filing in this sequence was filed on 02 Jun 2026.
Current net transaction value: -$784,776.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001507220 Primary reporting owner

Metzger Michael A

Relationship: Chief Executive Officer, Director
Address: C/O SYNDAX PHARMACEUTICALS, INC., 730 3RD AVENUE, FLOOR 9, NEW YORK
Signature: /s/ Michael A. Metzger
Signature date: 09 Jul 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

SNDX transaction

Common Stock

Options Exercise

Transaction value
Shares: +32,375
Change %: +6.7%
Price: $6.38^*
Shares after: 517,218
Date: 08 Jul 2026
Ownership: Direct

SNDX transaction

Common Stock

Sale

Transaction value: $784,776
Shares: -32,375
Change %: -6.3%
Price: $24.24
Shares after: 484,843
Date: 08 Jul 2026
Ownership: Direct
Footnotes: F1, F2

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

SNDX transaction Derivative

Stock Option (Right to buy)

Options Exercise

Transaction value
Shares: +32,375
Change %
Price: $0.000000^*
Shares after: 0
Date: 08 Jul 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 32,375
Exercise price: $6.38
Footnotes: F3

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Rule 10b5-1 trading plan

These transactions were reported as open-market trades under a Rule 10b5-1 plan. The plan lets an insider set trading instructions in advance, which can reduce the risk of trading while in possession of material nonpublic information.

Original filing language: transaction made pursuant to a contract, instruction, or written plan intended to satisfy Rule 10b5-1(c).

Explanation of responses 3 footnotes

Footnote F1

The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 plan adopted by the Reporting Person. Following the sales reported in this Form 4, the Reporting Person has a total of 1,564,551 options to purchase shares of common stock that are vested and immediately exercisable and a total of 813,949 options to purchase shares of common stock that have not yet vested.

Footnote F2

The sale prices ranged from $24.00 to $24.43

Footnote F3

This option is fully vested.