SPRO offering history
Every offering-related filing in Spero Therapeutics, Inc.’s recent SEC record — registrations (announced capacity) kept separate from pricing documents (executed sales). Reviewed 510 filings back to Mar 21, 2017.
| Date | Filing | What it means | |
|---|---|---|---|
| Mar 22, 2024 | EFFECT → | EFFECTIVE | SEC declared a registration effective — selling can begin |
| Mar 15, 2024 | S-3 → | REGISTERED | S-3 registration — capacity to sell shares, not a sale yet |
| Sep 22, 2022 | 8-K → | EXECUTED | Unregistered share sale disclosed (8-K item 3.02) |
| Jul 1, 2021 | 8-K → | EXECUTED | Unregistered share sale disclosed (8-K item 3.02) |
| Mar 29, 2021 | EFFECT → | EFFECTIVE | SEC declared a registration effective — selling can begin |
| Mar 11, 2021 | S-3 → | REGISTERED | S-3 registration — capacity to sell shares, not a sale yet |
| Nov 13, 2020 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Sep 14, 2020 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Sep 9, 2020 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Feb 11, 2020 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Jan 30, 2020 | 8-K → | EXECUTED | Unregistered share sale disclosed (8-K item 3.02) |
| Jun 14, 2019 | 424B5 → | EXECUTED | Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm) |
| Dec 11, 2018 | EFFECT → | EFFECTIVE | SEC declared a registration effective — selling can begin |
| Dec 3, 2018 | S-3 → | REGISTERED | S-3 registration — capacity to sell shares, not a sale yet |
| Nov 16, 2018 | 8-K → | EXECUTED | Unregistered share sale disclosed (8-K item 3.02) |
| Jul 13, 2018 | 424B4 → | EXECUTED | Final prospectus — offering priced (typical for IPOs and marketed share deals) |
| Jul 12, 2018 | EFFECT → | EFFECTIVE | SEC declared a registration effective — selling can begin |
| Jul 11, 2018 | S-1/A → | REGISTERED | S-1/A registration — capacity to sell shares, not a sale yet |
| Jul 9, 2018 | S-1 → | REGISTERED | S-1 registration — capacity to sell shares, not a sale yet |
| Nov 2, 2017 | 424B4 → | EXECUTED | Final prospectus — offering priced (typical for IPOs and marketed share deals) |
| Nov 1, 2017 | EFFECT → | EFFECTIVE | SEC declared a registration effective — selling can begin |
| Oct 23, 2017 | S-1/A → | REGISTERED | S-1/A registration — capacity to sell shares, not a sale yet |
| Oct 6, 2017 | S-1 → | REGISTERED | S-1 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.
SPRO offering FAQ
When did SPRO last execute an offering?
Per SEC filings, Spero Therapeutics, Inc.'s most recent priced offering document is a 8-K filed 2022-09-22. Note a 424B takedown can price shares or notes (debt) — the linked document says which.
When did SPRO last announce or register an offering?
The most recent registration is a S-3 filed 2024-03-15. 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.