Spero Therapeutics (SPRO)See Remarks sold ~$88K

~$88K

Approx. value · 37K sh @ $2.36

1.06M

Holds after · shares reported

Traded

Feb 6, 2026

Filed

Feb 10, 2026

The story around this disclosure

Every dated public record OQRO holds about the company from 60 days before to 120 days after, oldest first. It shows what was going on; none of it is a stated reason for the trade.

1. Jan 30, 2026Company filing · Form 8-K · Executive change, Other newsChanged a top executive or board member, and reported other company news“On January 30, 2026, Ankit Mahadevia, MD notified the Board of Directors (the “Board”) of Spero Therapeutics, Inc. (the “Company”) of his intention to resign from the Board, including from his service on the Development Committee of the Board and from all officer and director positions he holds with any and all subsidiaries of the Company, effective as of January 30, 2026.”
2. Feb 2, 2026Insider · 2 peopleInsiders: 2 sales (~$82K)
3. Feb 3, 2026InsiderOfficer sold ~$52K of SPRO shares in the open market
4. Feb 4, 2026InsiderOfficer sold ~$7.8K of SPRO shares in the open market
5. Feb 6, 2026 · this disclosureInsiderOfficer sold ~$88K of SPRO shares in the open market

What came next

1. Feb 6, 2026Insider · 2 peopleInsiders: 2 sales (~$164K)
2. Mar 26, 2026Company filing · Form 8-K · ResultsReported its results
3. May 4, 2026InsiderOfficer sold ~$63K of SPRO shares in the open market
4. May 13, 2026Company filing · Form 8-K · ResultsReported its results

How to read SEC Form 4

Form 4 is the filing that officers, directors and owners of more than 10% of a US-listed company must send to the SEC within two business days after they buy, sell or otherwise change their holding of the company's stock.

Full guide: What is an SEC Form 4?

What else is on file for Spero Therapeutics

OQRO holds no insider, Congress, fund or contract record for Spero Therapeutics dated in the last 90 days.

These are records OQRO holds, counted by their date, not a measure of how much trading took place. Routine paperwork such as option exercises and tax withholding is left out. Everything for the company is on its SPRO page.

Other recent filings by Esther Rajavelu, See Remarks

• SEC Form 4 at Spero Therapeutics (SPRO)May 7, 2026
• SEC Form 4 at Spero Therapeutics (SPRO)Feb 10, 2026
• SEC Form 4 at Spero Therapeutics (SPRO)Feb 5, 2026
• SEC Form 4 at Spero Therapeutics (SPRO)Nov 13, 2025
• SEC Form 4 at Spero Therapeutics (SPRO)Feb 6, 2025

The full history of Esther Rajavelu, See Remarks is on the profile page.

How this filing works

• SEC Form 4
• Open-market purchase
• Rule 10b5-1 trading plans

Other disclosures at Spero Therapeutics

• SEC Form 4May 7, 2026
• SEC Form 4Feb 10, 2026
• SEC Form 4Feb 10, 2026
• SEC Form 4Feb 5, 2026
• SEC Form 4Feb 5, 2026
• SEC Form 4Feb 5, 2026

Everything OQRO holds on this company is on its SPRO page.