Spero Therapeutics, Inc. SEC filings SPRO
Spero Therapeutics, Inc. has 515 filings in SEC EDGAR's recent list, going back to Mar 21, 2017. Its latest annual report, Form ARS, was filed on Apr 27, 2026 for the period ended Dec 31, 2025. The latest quarterly report (Form 10-Q) was filed on Aug 12, 2026, covering the quarter ended Jun 30, 2026. The most recent current report (Form 8-K) was filed on Oct 27, 2026 (officer or director change). The company's fiscal year ends on December 31.
| Form | Description | Filed | Period |
|---|---|---|---|
| DEFA14A | Additional proxy material | Apr 27, 2026 | — |
| DEF 14A | Proxy statement | Apr 27, 2026 | Jun 23, 2026 |
| PRE 14A | Preliminary proxy statement | Apr 13, 2026 | Jun 23, 2026 |
| DEFA14A | Additional proxy material | Apr 28, 2025 | — |
| DEF 14A | Proxy statement | Apr 28, 2025 | Jun 12, 2025 |
| DEFA14A | Additional proxy material | Apr 16, 2024 | — |
| DEF 14A | Proxy statement | Apr 16, 2024 | May 29, 2024 |
| DEF 14A | Proxy statement | Sep 1, 2023 | Oct 5, 2023 |
| PRE 14A | Preliminary proxy statement | Aug 22, 2023 | Oct 5, 2023 |
| DEFA14A | Additional proxy material | Aug 5, 2022 | — |
| DEF 14A | Proxy statement | Aug 5, 2022 | Sep 15, 2022 |
| DEF 14A | Proxy statement | Jul 6, 2021 | Aug 17, 2021 |
| PRE 14A | Preliminary proxy statement | Jun 25, 2021 | Aug 17, 2021 |
| DEF 14A | Proxy statement | Sep 30, 2020 | Oct 27, 2020 |
| DEF 14A | Proxy statement | Apr 26, 2019 | Jun 5, 2019 |
| DEF 14A | Proxy statement | Apr 27, 2018 | Jun 5, 2018 |
Showing 16 filings. Main filings leave out insider and ownership forms such as Form 4; choose a type above to see them. Each form opens on SEC.gov. Older filings are on SEC EDGAR.
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Company profile
- Industry
- Pharmaceutical Preparations (SIC 2834)
- Listed as
- SPRO (Nasdaq)
- Fiscal year ends
- December 31
- Incorporated in
- DE
- Headquarters
- Cambridge, MA
- SEC filer status
- Non-accelerated filer, Smaller reporting company
- SEC CIK
- 1701108
- Former names
- Spero Therapeutics, LLC (until Mar 21, 2017)
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Source: SEC EDGAR filings. This is company-reported data, not investment advice.