SPRO insider buying and SEC filings, explained
Spero Therapeutics, Inc. · CIK 1701108
Tracked: Forms 3/4/5, 8-K, NT · All filings on sec.gov
Insider activity in the last 12 months
Bought
$0
Insiders who bought
0
Sold (not marked 10b5-1)
$552K
Planned sales (10b5-1)
$0
Insider purchases and sales, last 12 months
| Traded | Type | What was filed | Source |
|---|---|---|---|
| May 4, 2026 | Sale | Esther Rajavelu (CEO) sold 25,240 shares at $2.51 ($63K). Holdings down 2% to 986,851 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed May 6, 2026 |
| Feb 6, 2026 | Sale | Esther Rajavelu (CEO) sold 87,917 shares at $2.36 ($207K). Holdings down 8% to 1,012,091 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 9, 2026 |
| Feb 6, 2026 | Sale | Timothy Keutzer (President / COO) sold 18,652 shares at $2.36 ($44K). Holdings down 2% to 742,506 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 9, 2026 |
| Feb 2–4, 2026 | Sale | Timothy Keutzer (President / COO) sold 46,586 shares between Feb 2 and Feb 4 at about $2.17 ($101K). Holdings down 6% to 761,158 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 5, 2026 |
| Feb 2, 2026 | Sale | Esther Rajavelu (CEO) sold 18,442 shares at $2.20 ($41K). Holdings down 2% to 1,100,008 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 4, 2026 |
| Nov 7, 2025 | Sale | Esther Rajavelu (CEO) sold 40,270 shares at $2.37 ($95K). Holdings down 4% to 869,450 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Nov 12, 2025 |
10 routine transactions (such as grants, option exercises or tax withholding) are not listed.
Cluster buys
No cluster buys in the last 12 months.
Red flags
No red flags in the last 12 months.
Key events
No key events in the last 12 months.
8-K filings, last 12 months
No 8-K filings in the last 12 months.
Red flags are objective triggers only: the item or form filed, never an opinion.
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