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Funds managed by Redmile Group, LLC exercised Atara Biotherapeutics pre-funded warrants on July 22, 2026 via a cashless exercise. The exercise delivered 195,211 shares of common stock to the funds, with 60 shares withheld to cover the exercise price. The funds continue to hold pre-funded warrants with low exercise prices ($0.0025 and $0.0001 per share), each limited by a 9.99% beneficial ownership blocker. Redmile and Jeremy Green report these as indirect holdings, disclaiming beneficial ownership beyond their pecuniary interest, and also correct prior warrant terms previously reported.
Atara Biotherapeutics, Inc. is the subject of an amended Schedule 13D/A filed by Redmile Group, LLC and related entities, updating their ownership after a warrant exercise. The reporting group may be deemed to beneficially own 950,994 shares of Atara common stock, representing 9.9% of the outstanding class.
The position consists of 636,852 shares held by Redmile-managed funds plus 314,142 shares issuable upon exercise of pre-funded warrants, capped by a 9.99% Beneficial Ownership Limitation. On July 16, 2026, Redmile effected a cashless exercise of certain warrants, leading to the issuance of 174,247 shares to Redmile Biopharma Investments II, L.P. and 20,904 shares to Redmile Strategic Long Only Trading Sub, Ltd., with small share amounts withheld to cover the exercise price. Redmile Strategic Long Only Trading Sub, Ltd. is reported to have ceased being a 5% beneficial owner on July 22, 2026.
Atara Biotherapeutics, Inc. reported that Kevin G. Sarney, serving as Interim CFO, filed an initial Form 3 statement of beneficial ownership. The filing lists him as an officer but shows no reported transactions or holdings details in the provided data.
Atara Biotherapeutics, Inc. reported leadership changes in its finance organization. The company notified Chief Accounting Officer Yanina Grant-Huerta that her employment will end effective July 17, 2026. This affects oversight of financial reporting and accounting.
Effective June 26, 2026, the board appointed Kevin G. Sarney of Charles River CFO, Inc. as interim chief financial officer. He will also serve as principal financial officer and principal accounting officer under a consulting agreement with CRCFO, which can be terminated by either party with 30 days’ written notice. Mr. Sarney brings over 25 years of life science finance and accounting experience and will enter into Atara’s standard indemnification agreement for executive officers.
Cherry Brian N reported acquisition or exercise transactions in this Form 4 filing.
Atara Biotherapeutics director Brian N. Cherry received a grant of 24,000 shares of common stock on June 11, 2026 as a compensation award. The shares are in the form of restricted stock units that vest in three equal annual installments on the first, second, and third anniversaries of June 11, 2026, subject to his continuous service. Following this grant, Cherry directly holds 62,320 shares of Atara common stock.
Atara Biotherapeutics, Inc. director Brian N. Cherry filed an initial ownership report showing his holdings in the company’s common stock. The filing lists direct ownership of 38,320 shares of Common Stock after the reported holdings, with no specific buy or sell transaction disclosed.
Atara Biotherapeutics, Inc. reported governance updates from its June 2026 shareholder meeting and a new board appointment. The board named Brian Cherry as a Class I director effective June 11, 2026, and appointed him to the Audit Committee. He will receive an initial grant of 24,000 restricted stock units vesting annually over three years, plus an annual cash retainer of $55,000 under the non‑employee director program.
Stockholders elected two directors to terms running until the 2029 annual meeting, approved on an advisory basis the compensation of named executive officers, and approved an amendment to the 2024 Equity Incentive Plan. They also ratified Deloitte & Touche LLP as independent registered public accounting firm for the fiscal year ending December 31, 2026.
HEIDEN WILLIAM K reported acquisition or exercise transactions in this Form 4 filing.
Atara Biotherapeutics director William K. Heiden received a grant of 12,000 shares of Common Stock in the form of restricted stock units as compensation. The award was recorded at a price of $0.00 per share and is not an open-market purchase.
These restricted stock units will vest on the earlier of June 9, 2027 or the date of the next annual meeting of stockholders, provided he maintains continuous service. Following this grant, Heiden directly holds 34,188 shares of Atara Biotherapeutics common stock.
Fust Matthew K reported acquisition or exercise transactions in this Form 4 filing.
Atara Biotherapeutics director Matthew K. Fust received an equity award of 12,000 shares of common stock in the form of restricted stock units. The award was granted at no cash cost and will vest on the earlier of June 9, 2027 or the next annual stockholder meeting, subject to his continuous service. Following this grant, he holds 30,188 shares directly.
Ciongoli Gregory Austin reported acquisition or exercise transactions in this Form 4 filing.
Atara Biotherapeutics director Gregory A. Ciongoli reported an equity compensation award and updated his indirect holdings. He received a grant of 12,000 shares of common stock as a restricted stock unit award at a price of $0.00 per share.
These restricted stock units vest on the earlier of June 9, 2027 or the date of the next annual meeting of stockholders, subject to his continuous service. The filing also reports 1,209,395 shares of common stock indirectly held by Adiumentum Capital Fund I LP, a Delaware limited partnership with which Ciongoli and its general partner are associated, while all parties disclaim beneficial ownership except to the extent of any pecuniary interest.