Rajavelu Esther 4

What Happened

• Rajavelu Esther, listed as Chief Executive Officer, Chief Financial Officer and Chief Business Officer of Spero Therapeutics (SPRO), received two equity awards on 2026-02-02: 249,000 restricted stock units (RSUs) and a 498,000-share derivative award (option-based). Both awards were reported at $0.00 acquisition price (typical for grants).
• On the same date she disposed of 18,442 shares in an open-market sale at $2.20 per share, for proceeds of $40,572. That sale was executed automatically to cover tax withholding associated with RSU vesting (a "sell-to-cover"), not a discretionary sale.

Key Details

• Transaction date: February 2, 2026; Form 4 filed February 4, 2026 (filed within the standard 2-business-day window).
• Sale: 18,442 shares @ $2.20 = $40,572 (footnote: sell-to-cover for tax withholding; not a discretionary trade).
• Grants: 249,000 RSUs (F1) and 498,000 derivative/option-based shares (F3), both reported as acquisitions @ $0.00.
• Vesting notes:
  • RSUs (249,000): vest in four equal annual installments beginning Feb 2, 2027, subject to continued service (F1).
  • Derivative/option (498,000): vests 25% on Feb 2, 2027, then monthly over 36 months thereafter, subject to continued service (F3).
• Shares owned after the transactions: not disclosed in the information provided in this summary.
• Filing timeliness: filing appears timely (reported within the normal Form 4 window).

Context

• The 18,442-share sale was a sell-to-cover to satisfy tax withholding on RSU vesting and is explicitly noted as not representing a discretionary trade; such transactions are common and typically don’t indicate a change in insider sentiment.
• The larger grants are forward-looking compensation (RSUs and option-based awards) with multi-year vesting schedules rather than immediate share transfers; they represent potential future ownership if vesting conditions are met.