Adiumentum Capital Fund I LP - 16 May 2025 Form 4 Insider Report for Atara Biotherapeutics, Inc. (ATRA)

Reporting relationship: Director, Other*, 10%+ Owner
Issuer ticker: ATRA
Reported as of: 16 May 2025
Net transaction value: +$1,999,978
SEC form: 4
Accepted by SEC: 16 May 2025, 18:26:21 UTC
Prior SEC filing: 05 Sep 2024
Source filing: View source filing
Reporting owner signature: Adiumentum Capital Fund I LP By: /s/ Gregory A. Ciongoli, Managing Partner

Key filing fact

Adiumentum Capital Fund I LP filed Form 4 for Atara Biotherapeutics, Inc. (ATRA) on 16 May 2025.

Key facts

This page summarizes Adiumentum Capital Fund I LP's Form 4 filing for Atara Biotherapeutics, Inc. (ATRA).
2 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 16 May 2025, 18:26.

Change

Previous filing in this sequence was filed on 05 Sep 2024.
Current net transaction value: +$1,999,978.

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 (3)

CIK 0002023734 Primary reporting owner

Adiumentum Capital Fund I LP

Relationship: Director, Other*, 10%+ Owner
Address: C/O ROPES & GRAY LLP, 800 BOYLSTON ST., BOSTON
Signature: Adiumentum Capital Fund I LP By: /s/ Gregory A. Ciongoli, Managing Partner
Signature date: 16 May 2025

CIK 0002023736

Adiumentum Capital Fund I GP LLC

Relationship: Director, Other*, 10%+ Owner
Address: C/O ROPES & GRAY LLP, 800 BOYLSTON ST., BOSTON
Signature: Adiumentum Capital Fund I GP LLC By: /s/ Gregory A. Ciongoli, Managing Member
Signature date: 16 May 2025

CIK 0002023732

Ciongoli Gregory Austin

Relationship: Director, Other*, 10%+ Owner
Address: C/O ROPES & GRAY LLP, 800 BOYLSTON ST., BOSTON
Signature: /s/ Gregory A. Ciongoli
Signature date: 16 May 2025

Reported non-derivative transactions

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

ATRA transaction

Common Stock

Award

Transaction value: $499,531
Shares: +75,572
Change %: +6.7%
Price: $6.61
Shares after: 1,209,395
Date: 16 May 2025
Ownership: Direct
Footnotes: F1, F2

Reported derivative securities

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

ATRA transaction Derivative

Warrants (right to buy)

Award

Transaction value: $1,500,447
Shares: +227,000
Change %: +151%
Price: $6.61
Shares after: 377,193
Date: 16 May 2025
Ownership: Direct
Underlying class: Common Stock
Underlying amount
Exercise price: $0.000100
Footnotes: F1, F2, F3, F4, F5

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

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 5 footnotes

Footnote F1

In addition to Adiumentum Capital Fund I LP, a limited partnership organized under the laws of Delaware ("Adiumentum"), this Form 4 is being filed jointly by Adiumentum Capital Fund I GP LLC, a limited liability company organized under the laws of Delaware and the general partner of Adiumentum ("Adiumentum GP"), and Gregory A. Ciongoli, a citizen of the United States of America and the managing member of Adiumentum GP (together with Adiumentum and Adiumentum GP, the "Reporting Persons"). Each of the Reporting Persons has the same business address as Adiumentum and may be deemed to have a pecuniary interest in securities reported on this Form 4 (the "Subject Securities"). Each of the Reporting Persons disclaims any beneficial ownership of any of the Subject Securities, except to the extent of any pecuniary interest therein.

Footnote F2

Adiumentum may be deemed to have the shared power to vote or direct the vote of (and the shared power to dispose or direct the disposition of) all of the Subject Securities. Adiumentum GP, as the general partner of Adiumentum may be deemed to have the shared power to vote or direct the vote of (and the shared power to dispose or direct the disposition of) all the Subject Securities. Mr. Ciongoli, as the managing partner of Adiumentum, and as the managing member of Adiumentum GP, may be deemed to have the shared power to vote or direct the vote of (and the shared power to dispose or direct the disposition of) all the Subject Securities.

Footnote F3

The warrants are immediately exercisable and do not expire.

Footnote F4

Pursuant to the terms of the warrants, the Issuer may not effect any exercise of any warrant, and a holder of a warrant does not have the right to exercise any portion of the warrant held by such holder, to the extent that, after giving effect to the attempted exercise set forth in a notice of exercise, such holder, together with such holder's affiliates and any other person whose beneficial ownership of common stock, par value $0.0001 per share (the "Common Stock"), of the Issuer would be aggregated with such holder's for the purposes of Section 13(d) of the Exchange Act, and the applicable regulations of the U.S. Securities and Exchange Commission (the "SEC"), including any "group" of which such holder is a member, would beneficially own a number of shares of Common Stock in excess of the Beneficial Ownership Limitation.

Footnote F5

The "Beneficial Ownership Limitation" is 19.99% of the shares of Common Stock then issued and outstanding, which percentage may be changed at a holder's election upon 61 days' notice to the Issuer.

SEC remarks

Mr. Ciongoli serves as a director on the Board of Directors of the Issuer and, as a result, the entities listed in these notes are directors by deputization for purposes of Section 16 of the Securities Exchange Act of 1934, as amended (the "Exchange Act").