ATRA offering history
Every offering-related filing in Atara Biotherapeutics, Inc.’s recent SEC record — registrations (announced capacity) kept separate from pricing documents (executed sales). Reviewed 1,004 filings back to Jul 7, 2015.
| Date | Filing | What it means | |
|---|---|---|---|
| May 12, 2026 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Mar 25, 2026 | 424B3 → | UPDATE | Prospectus update — often a resale registration, not necessarily new capital |
| Mar 25, 2026 | EFFECT → | EFFECTIVE | SEC declared a registration effective — selling can begin |
| Mar 17, 2026 | S-3 → | REGISTERED | S-3 registration — capacity to sell shares, not a sale yet |
| Mar 16, 2026 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Feb 23, 2026 | 8-K → | EXECUTED | Unregistered share sale disclosed (8-K item 3.02) |
| May 15, 2025 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Sep 4, 2024 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Jan 9, 2024 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Nov 17, 2023 | 424B3 → | UPDATE | Prospectus update — often a resale registration, not necessarily new capital |
| Nov 13, 2023 | EFFECT → | EFFECTIVE | SEC declared a registration effective — selling can begin |
| Nov 1, 2023 | S-3 → | REGISTERED | S-3 registration — capacity to sell shares, not a sale yet |
| Feb 13, 2023 | EFFECT → | EFFECTIVE | SEC declared a registration effective — selling can begin |
| Nov 26, 2021 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Mar 1, 2021 | S-3ASR → | REGISTERED | Automatic shelf registration — effective immediately (large filers) |
| Dec 9, 2020 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Dec 7, 2020 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| May 27, 2020 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| May 26, 2020 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Feb 27, 2020 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Jul 19, 2019 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Jul 18, 2019 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Feb 26, 2019 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Mar 1, 2018 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Feb 27, 2018 | S-3ASR → | REGISTERED | Automatic shelf registration — effective immediately (large filers) |
| Feb 27, 2018 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Jan 4, 2018 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Jan 3, 2018 | FWP → | MARKETING | Free-writing prospectus — offering being marketed |
| Jan 2, 2018 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Mar 27, 2017 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Nov 23, 2015 | EFFECT → | EFFECTIVE | SEC declared a registration effective — selling can begin |
| Nov 9, 2015 | S-3 → | REGISTERED | S-3 registration — capacity to sell shares, not a sale yet |
| Jul 10, 2015 | 424B1 → | EXECUTED | Prospectus supplement priced — shares or notes (large filers: often a bond deal) |
| Jul 9, 2015 | S-1/A → | REGISTERED | S-1/A registration — capacity to sell shares, not a sale yet |
| Jul 9, 2015 | S-1MEF → | REGISTERED | S-1MEF registration — capacity to sell shares, not a sale yet |
| Jul 9, 2015 | EFFECT → | EFFECTIVE | SEC declared a registration effective — selling can begin |
| Jul 7, 2015 | S-1/A → | REGISTERED | S-1/A registration — capacity to sell shares, not a sale yet |
Two honest limits. (1) A 424B takedown can price shares or notes— EDGAR’s metadata doesn’t say which, so open the document: large investment-grade filers use these mostly for bond deals (no dilution), small-caps mostly for shares. (2) At-the-market (ATM) programs sell shares gradually and individual sales are not separately filed — the visible footprint is the enabling shelf and its 424B5; actual ATM share counts surface later in the 10-Q/10-K share count. Educational information from public filings, not investment advice.
ATRA offering FAQ
When did ATRA last execute an offering?
Per SEC filings, Atara Biotherapeutics, Inc.'s most recent priced offering document is a 424B5 filed 2026-05-12. Note a 424B takedown can price shares or notes (debt) — the linked document says which.
When did ATRA last announce or register an offering?
The most recent registration is a S-3 filed 2026-03-17. A registration is capacity to sell shares — not a sale.
Does an offering always mean dilution?
Registered direct offerings and shelf takedowns issue new shares and dilute existing holders. Resale registrations (424B3/B7) let existing holders sell and do not create new shares. Secondary sales by insiders also do not dilute. Each row here is labeled with what it is.