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Atara Biotherapeutics has amended its royalty purchase agreement with HealthCare Royalty (HCRx), pushing back a one-time $9.0 million milestone payment from June 30, 2026 to January 1, 2028. This later due date eases near-term cash obligations tied to its commercialization agreement with Pierre Fabre Medicament.
In return, Atara issued HCRx a warrant to purchase up to 400,000 shares of common stock at an exercise price of $0.0001 per share. The warrant is immediately exercisable, has no expiration date, and includes a 4.99% beneficial ownership cap, with the option for cashless exercise. Atara plans to register the resale of the underlying shares in a future registration statement.
Panacea-affiliated investors filed Amendment No. 2 to a Schedule 13D reporting their stake in Atara Biotherapeutics’ common stock. Panacea Innovation Limited and related entities report beneficial ownership of 1,632,345 shares, or 19.99% of Atara’s common stock, including 259,163 warrants that are immediately exercisable and do not expire. Based on 7,258,971 shares outstanding as of November 28, 2025, they may exercise warrants to purchase 97,345 shares without exceeding the 19.99% ownership cap.
Panacea Venture Healthcare Fund II, L.P. holds 1,324,446 shares, representing 18.2% of the class, while Panacea Opportunity Fund I, L.P. holds 307,899 shares, or 4.1%. On November 28, 2025, Panacea Opportunity Fund I, L.P. exercised warrants for 48,736 shares after tax withholding, and on January 12, 2026, Panacea Venture Healthcare Fund II, L.P. sold 80,554 shares in open market transactions at a weighted average price of $6.0707 per share.
Panacea-affiliated investment funds reported an insider sale of Atara Biotherapeutics, Inc. common stock. On January 12, 2026, Panacea Venture Healthcare Fund II, L.P. sold 80,554 shares of Atara common stock in an open-market transaction at a weighted average price of $6.0707 per share, with individual trades ranging from $5.9888 to $6.2838.
After this sale, Panacea Venture Healthcare Fund II, L.P. held 1,324,446 shares of Atara common stock indirectly for the reporting persons, and Panacea Opportunity Fund I, L.P. held an additional 48,736 shares. Panacea Innovation Ltd and James Huang are reporting persons because of their control of the general partners of these funds and may be deemed to share beneficial ownership of these holdings, although each disclaims such beneficial ownership.
Atara Biotherapeutics, Inc. (ATRA) has a shareholder filing a notice of proposed sales of common stock under Rule 144. The notice lists planned sales of 40,000 shares through Cantor Fitzgerald, 20,000 shares through Jefferies, and 20,554 shares through JP Morgan, all as common stock traded on NASDAQ, with an approximate sale date of 01/12/2026. The corresponding aggregate market values are stated as 235,200, 117,600.00, and 120,858.00, respectively. The filing notes that 7,210,235 shares of common stock are outstanding. The seller reports having acquired 1,405,000 shares of common stock on 08/15/2025, through multiple open market purchases from January 2025 through August 2025 and a registered direct financing in May 2025, paid in cash.
Atara Biotherapeutics, Inc. filed a current report describing two developments. The company provided a preliminary estimate of its cash, cash equivalents and short-term investments as of December 31, 2025, explaining that this early figure does not include all information needed to fully understand its year-end financial condition or fourth-quarter results.
Atara also reported that the U.S. Food and Drug Administration issued a Complete Response Letter for the Biologics License Application for EBVALLO™ (tabelecleucel). This means the application was not approved in its current form and further action would be required before EBVALLO could be considered again for U.S. approval. The company disclosed this regulatory and business update via a press release attached as an exhibit.
Atara Biotherapeutics (ATRA) President and CEO AnhCo Nguyen, who also serves as a director, reported an automatic sale of company common stock related to tax withholding on vested restricted stock units. On 11/17/2025, Nguyen sold 2,859 shares of common stock at a weighted average price of $13.186 per share and an additional 56 shares at a weighted average price of $13.188 per share. These transactions were carried out by a broker as part of a group sale for multiple employees to satisfy withholding tax liabilities tied to equity awards. Following the transactions, Nguyen directly beneficially owned 64,974 shares of Atara Biotherapeutics common stock.
Atara Biotherapeutics, Inc. reported insider share sales by an officer related to tax withholding. The company’s Chief Accounting Officer, Yanina Grant-Huerta, reported three sales of Atara common stock on 11/17/2025 totaling 1,804 shares at weighted average prices between $13.186 and $13.191 per share. After these transactions, she beneficially owned 33,454 shares of common stock directly.
The filing explains that the shares were sold automatically under a sale-to-cover provision to satisfy tax withholding obligations upon the vesting of previously granted restricted stock units, with prices reflecting broker-handled sales for a group of employees on that date.
Atara Biotherapeutics (ATRA) reported Q3 2025 results marked by lower revenue and a smaller operating footprint after transferring tab-cel responsibilities to Pierre Fabre. Commercialization revenue was $3.5 million, with a net loss of $4.3 million and loss from operations of $3.6 million.
Liquidity narrowed: cash and cash equivalents were $5.7 million and short‑term investments $8.0 million at September 30, 2025. Total assets were $30.2 million against total liabilities of $66.8 million, leaving a stockholders’ deficit of $36.6 million. Deferred revenue declined to $1.0 million as the company recognized prior amounts tied to its Pierre Fabre agreements.
Management concluded that substantial doubt exists about the company’s ability to continue as a going concern and outlined plans to seek additional capital, including equity facilities, debt, and strategic transactions. During 2025, Atara completed the transfer of manufacturing, clinical, development, and regulatory responsibilities for tab‑cel to Pierre Fabre. The company noted the tab‑cel BLA is tracking toward a PDUFA target action date of January 10, 2026. Shares outstanding were 7,210,235 as of November 6, 2025.
Atara Biotherapeutics furnished a current report announcing its financial results and operational progress for the quarter ended September 30, 2025. The details are provided in a press release titled “Atara Biotherapeutics Announces Third Quarter Financial Results and Operational Progress,” included as Exhibit 99.1.
The company states this information is furnished, not filed, and is therefore not subject to Section 18 of the Exchange Act or Sections 11 and 12(a)(2) of the Securities Act, unless specifically incorporated by reference. Atara’s common stock trades on Nasdaq under the symbol ATRA.
Atara Biotherapeutics, Inc. reported a significant workforce reduction, cutting approximately 29% of its current employees and retaining about 15 employees who are considered essential to its strategic priorities. The reduction in force is expected to be completed by January 2026.
The company expects to recognize about $1.3 million in severance and related benefits tied to this action. Approximately half of these charges relate to salary continuation and wages for the 60-day notice period required under the California Worker Adjustment and Retraining Notification Act. The company notes that it may incur additional charges or cash expenditures related to this workforce reduction, with further details to be provided in its Quarterly Report on Form 10-Q for the period ending September 30, 2025.