Legal Insider Trading Data | Free and Professional Subscription Services | Insider Insights urn:uuid:e9d992c1-0414-315f-b989-7f7daabcb82c 2026-07-15T05:40:16-04:00 Jonathan Moreland Profit from legal insider trading. InsiderInsights.com provides free insider trading data tools and resources, and professional grade subscription based real time Form 4 data, analysis and services ATRA: SARNEY KEVIN G (CFO) Filed a Form 3, Becoming a Registered Insider at ATARA BIOTHERAPEUTICS INC With Initial Holdings of 0 urn:uuid:f8dbddfc-54d0-c4c4-9523-5bdd1bb5971f 2026-07-06T16:14:19-04:00 ATRA: CHERRY BRIAN N (DIR) Acquired (JB) 24k Shares of ATARA BIOTHERAPEUTICS INC for $0.00 on 6/11 urn:uuid:182a4a92-2372-e74f-3667-a920bee39ef1 2026-06-15T18:51:31-04:00 ATRA: CHERRY BRIAN N (DIR) Filed a Form 3, Becoming a Registered Insider at ATARA BIOTHERAPEUTICS INC With Initial Direct Holdings of 38,320 urn:uuid:eb6e3b19-7c9f-c8df-bb69-d99d346fc59b 2026-06-15T18:48:52-04:00 ATRA: HEIDEN WILLIAM K (DIR) Acquired (JB) 12k Shares of ATARA BIOTHERAPEUTICS INC for $0.00 on 6/9 urn:uuid:28159955-97b4-50e3-52c5-41e90dc4b756 2026-06-11T16:37:50-04:00 ATRA: FUST MATTHEW K (DIR) Acquired (JB) 12k Shares of ATARA BIOTHERAPEUTICS INC for $0.00 on 6/9 urn:uuid:5d29ed84-260d-f3f3-3b63-7f12f13be562 2026-06-11T16:36:58-04:00 ATRA: CIONGOLI GREGORY AUSTIN (DIR,BO) Acquired (JB) 12k Shares of ATARA BIOTHERAPEUTICS INC for $0.00 on 6/9 urn:uuid:509a5223-dcde-f74f-58ee-762fc690054c 2026-06-11T16:36:04-04:00 ATRA: NGUYEN ANHCO (PR,CEO,DIR) Sold (S) 5,241 Shares of ATARA BIOTHERAPEUTICS INC for $9.13 on 5/18 urn:uuid:963f847d-ba68-d981-0a0c-41f2db4dd9c9 2026-05-20T17:24:39-04:00 ATRA: GRANT HUERTA YANINA (CAO) Sold (S) 2,414 Shares of ATARA BIOTHERAPEUTICS INC for $9.13 on 5/18 urn:uuid:69ebd0b1-f272-09b9-d7eb-f1607b5acf9c 2026-05-20T17:24:23-04:00 ATRA: PANACEA INNOVATION LTD (BO) Sold (S) 313,446 Shares of ATARA BIOTHERAPEUTICS INC for $10.10 on 5/7 urn:uuid:b49b377d-9902-8c16-5722-b2361affe056 2026-05-11T18:45:04-04:00 ATRA: ECOR1 CAPITAL LLC (BO) Bought (B) 507,407 Shares of ATARA BIOTHERAPEUTICS INC for $9.35 on 5/7 urn:uuid:6dad022a-0a39-6e22-90a8-4b384f7bcfb1 2026-05-11T17:34:20-04:00