Atara Biotherapeutics, Inc. (ATRA)
Nasdaq: ATRA · Biological Products, (No Diagnostic Substances) · Thousand Oaks, CA · filing with the SEC since 2014
Filings
348 filings since 2017 beside 504 insider forms · Non-accelerated filer and smaller reporting company · read from EDGAR on Nov 13, 2026Due nextNon-accelerated filer and smaller reporting company
10-K
Annual report for the fiscal year ending Dec 31, 2026Non-accelerated filers and smaller reporting companies have 90 days after the fiscal year ends.
by Mar 31, 2027
10-Q
Quarterly report for the quarter ending Mar 31, 2027Non-accelerated filers and smaller reporting companies have 45 days after the quarter ends; quarter ends are taken to the month end.
by May 15, 2027
A deadline is the latest date the SEC's rules allow for its filer category. It is not a forecast of the day the company files. Last time, the results release (8-K item 2.02) came 41 days after the quarter ended. The proxy statement was last filed Apr 24, 2026.
Filings a yearinsider forms included
8270836385966763
2026 counts to Nov 13, 2026.
Officer or director change (8-K item 5.02): 12 times in the last 36 months, the newest Jun 26, 2026.Listing warning from its exchange (8-K item 3.01): 2 times in the last 36 months, the newest May 1, 2026.SEC letters: 2 in the last 36 months, the newest Mar 23, 2026.
Insider forms (3, 4, 5 and 144) are counted each year but not listed here; the people and their trades are on the Ownership tab.
FiledFormWhat it is, in plain wordsPeriodAsk
Jun 12, 2026
8-K items 5.02, 5.07
Officer or director change; Shareholder vote · Current report
Jun 9, 2026
Feb 23, 2026
8-K items 1.01, 3.02, 8.01, 9.01
Major agreement signed; Shares sold without registration; Other event · Current report
Feb 20, 2026
40 of 348 shown
Every row opens the filing on EDGAR. The plain words are the site's own for each form and each 8-K item; the complete history, insider forms included, is on EDGAR.