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Atara Biotherapeutics, Inc. reported an insider filing showing that investment entities associated with Panacea Innovation executed an open-market sale of 313,446 shares of common stock at a weighted average price of $10.0975 per share, with individual trades between $10.00 and $10.50. The shares sold were held by Panacea Venture Healthcare Fund II, L.P. Following the sale, entities associated with Panacea report indirect holdings of 1,011,000 shares in one position and 307,894 shares in another. James Huang and Panacea Innovation Limited may be deemed to share beneficial ownership of these fund holdings, but each expressly disclaims beneficial ownership.
EcoR1 Capital, LLC, a ten percent owner of Atara Biotherapeutics, reported an indirect open-market purchase of 507,407 shares of Common Stock at a weighted average price of $9.35 per share. The shares were bought by funds it advises, which now hold 1,552,000 shares in total.
EcoR1 Capital, LLC filed an initial Form 3 reporting its status as a more than ten percent owner of Atara Biotherapeutics, Inc. common stock. The filing shows indirect beneficial ownership of 1,044,593 shares, with EcoR1-related Qualified Fund holding 970,829 shares for the benefit of its investors.
Atara Biotherapeutics received a Schedule 13G reporting that Point72-affiliated entities beneficially own 526,682 shares of Common Stock, representing 6.2% of the class as of May 7, 2026. The filing states Point72 Asset Management, Point72 Capital Advisors Inc., and Steven A. Cohen share voting and dispositive power over these shares through Point72 Associates under a joint filing agreement. The reporting persons own no shares directly and the disclosure notes Point72 Associates has the right to receive dividends or sale proceeds for the reported position.
ATRA reported a proposed sale of 1,405,000 shares of Common Stock via a Form 144. The filing states the shares were purchased in multiple open‑market transactions from January 2025 through August 2025 and in a registered direct financing in May 2025, with planned brokerage transactions on 08/15/2025.
EcoR1 Capital and related filers reported passive ownership stakes in Atara Biotherapeutics. The filing shows EcoR1 Capital, LLC and Oleg Nodelman each report 1,552,000 shares (representing 17.4% of the class) and EcoR1 Capital Fund Qualified, L.P. reports 1,445,609 shares (16.2%), based on 8,912,272 shares outstanding as of May 7, 2026. The filing states excluded warrants to acquire 1,090,922 and 1,026,558 shares respectively that are subject to a 9.99% beneficial ownership limitation and currently cannot be exercised.
Atara Biotherapeutics reported a regulatory update on tabelecleucel (tab-cel) after a recent Type A meeting with the FDA following the Complete Response Letter issued on January 9, 2026 for its Biologics License Application held by partner Pierre Fabre Pharmaceuticals.
The FDA agreed that a single-arm study using an appropriate pre-specified historical control could be considered an adequate and well-controlled study to provide safety and efficacy data for a future marketing application in relapsed or refractory EBV+ PTLD after transplant in patients two years of age and older.
Pierre Fabre plans to submit an updated dataset with additional patients and longer follow-up from the pivotal Phase 3 ALLELE study, along with supportive data, as part of a resubmission plan being defined with the FDA. Atara expects to provide a further regulatory update in the third quarter.
Atara Biotherapeutics, Inc. received a Nasdaq notice that it no longer meets the $50 million minimum market value of listed securities (MVLS) required for continued listing on the Nasdaq Global Select Market.
Nasdaq reviewed the company’s market value over the last 30 consecutive business days and found it below this threshold. Atara has until October 27, 2026 (a 180-day compliance period) to regain compliance. If its MVLS closes at or above $50 million for at least 10 consecutive business days (and potentially up to 20 days at Nasdaq’s discretion), Nasdaq will confirm renewed compliance. The company’s shares continue trading under the symbol “ATRA” while it evaluates options, which may include applying to transfer to the Nasdaq Capital Market. If compliance is not regained by the deadline, Nasdaq may move to delist the shares, a decision Atara could appeal to a Hearings Panel.
Atara Biotherapeutics is asking stockholders to vote at its virtual 2026 annual meeting on June 9, 2026. Holders of 8,512,272 shares of common stock as of April 14, 2026 can participate online using a 16-digit control number.
Stockholders will elect two directors to terms ending in 2029, cast an advisory vote on named executive officer compensation, and vote on amending the 2024 Equity Incentive Plan to add 400,000 shares to the reserve, bringing total availability to 469,657 shares. They will also vote on ratifying Deloitte & Touche LLP as independent auditor for 2026. The proxy explains virtual meeting logistics, quorum and voting standards, broker non-votes, and outlines Atara’s board structure, independence, ESG oversight, cybersecurity framework and key governance policies, including stock ownership guidelines, clawback and anti-hedging rules.