Atara Biotherapeutics, Inc. - ATRA
All tracked SEC files for this issuer. Showing up to 200 latest records.
Need parsed ownership details (13D/13G with shares/percent)?
Open ownership details
Form 4 = insider transactions report. Form 144 = notice of proposed sale (not a completed trade confirmation).
Files summary
Total files loaded: 37
Latest filed: Jun 26, 2026
| Form | Count |
|---|---|
| 4 | 14 |
| 8-K | 11 |
| 144 | 6 |
| SCHEDULE 13D/A | 3 |
| SCHEDULE 13G | 2 |
| SCHEDULE 13G/A | 1 |
Latest files
| Filed | Form | Report period | Accession | SEC |
|---|---|---|---|---|
| Jun 26, 2026 | 8-K | Jun 22, 2026 | 0001193125-26-285498 | View |
| Jun 15, 2026 | 4 | Jun 11, 2026 | 0000905148-26-002951 | View |
| Jun 12, 2026 | 8-K | Jun 09, 2026 | 0001213900-26-068264 | View |
| Jun 11, 2026 | 4 | Jun 09, 2026 | 0000905148-26-002919 | View |
| Jun 11, 2026 | 4 | Jun 09, 2026 | 0000905148-26-002920 | View |
| Jun 11, 2026 | 4 | Jun 09, 2026 | 0000905148-26-002921 | View |
| May 20, 2026 | 4 | May 18, 2026 | 0000905148-26-002570 | View |
| May 20, 2026 | 4 | May 18, 2026 | 0000905148-26-002571 | View |
| May 18, 2026 | 144 | — | 0000905148-26-002506 | View |
| May 18, 2026 | 144 | — | 0000905148-26-002507 | View |
| May 14, 2026 | SCHEDULE 13D/A | — | 0001104659-26-061506 | View |
| May 13, 2026 | SCHEDULE 13G | — | 0000919574-26-002914 | View |
| May 12, 2026 | 8-K | May 12, 2026 | 0001193125-26-219420 | View |
| May 11, 2026 | 4 | May 07, 2026 | 0001193125-26-217380 | View |
| May 11, 2026 | SCHEDULE 13D/A | — | 0001193125-26-217389 | View |
| May 11, 2026 | 4 | May 07, 2026 | 0000935836-26-000239 | View |
| May 08, 2026 | SCHEDULE 13G | — | 0000919574-26-002802 | View |
| May 07, 2026 | 144 | — | 0001193125-26-212781 | View |
| May 07, 2026 | SCHEDULE 13G/A | — | 0000935836-26-000230 | View |
| May 07, 2026 | 8-K | May 07, 2026 | 0001193125-26-210413 | View |
| May 01, 2026 | 8-K | Apr 30, 2026 | 0001193125-26-201397 | View |
| Mar 19, 2026 | 4 | Mar 17, 2026 | 0001193125-26-116060 | View |
| Mar 16, 2026 | 8-K | Mar 16, 2026 | 0001193125-26-108344 | View |
| Mar 12, 2026 | 8-K | Mar 12, 2026 | 0001193125-26-103127 | View |
| Mar 11, 2026 | 4 | Mar 09, 2026 | 0000905148-26-001224 | View |
| Mar 11, 2026 | 4 | Mar 09, 2026 | 0000905148-26-001225 | View |
| Mar 04, 2026 | 4 | Mar 02, 2026 | 0000905148-26-001143 | View |
| Mar 04, 2026 | 4 | Mar 02, 2026 | 0000905148-26-001144 | View |
| Mar 03, 2026 | 8-K | Mar 03, 2026 | 0001193125-26-086793 | View |
| Mar 02, 2026 | 144 | — | 0000905148-26-001100 | View |
| Mar 02, 2026 | 144 | — | 0000905148-26-001102 | View |
| Feb 23, 2026 | 8-K | Feb 20, 2026 | 0001193125-26-062534 | View |
| Jan 14, 2026 | SCHEDULE 13D/A | — | 0001193125-26-013362 | View |
| Jan 14, 2026 | 4 | Jan 12, 2026 | 0001193125-26-013358 | View |
| Jan 12, 2026 | 8-K | Jan 12, 2026 | 0001193125-26-010342 | View |
| Jan 12, 2026 | 144 | — | 0001193125-26-010883 | View |
| Jan 02, 2026 | 8-K | Dec 30, 2025 | 0001193125-26-000907 | View |