Horizon Quantum (HQ) Chief Science Officer Tan Si‑Hui Sells 2,991 Shares

What Happened

• Dr. Tan Si‑Hui, Chief Science Officer of Horizon Quantum Holdings Ltd. (HQ), had 5,728 RSUs vest on Sept 12, 2026. Of those vested RSUs, 2,991 were settled in cash to the company at $15.22 per share (the Sept 11, 2026 closing price), producing $45,523 in proceeds. The filing also reports multiple RSU grants (including a 91,659‑unit grant on June 12, 2026 and earlier legacy option/option-exchange activity tied to the March 19, 2026 business combination).
• Several reported acquisitions are grants of unvested RSUs (and an exchange of legacy options), not open‑market purchases. The cash settlement of a portion of the vested RSUs is effectively a cashless/withholding style settlement rather than a a market sale.

Key Details

• Transaction dates and amounts:
  • Sept 12, 2026: 5,728 RSUs vested; 2,991 shares settled to issuer at $15.22 each = $45,523 (cash settlement). The remaining vested RSUs were converted to shares (acquired at $0 in reporting terms).
  • June 12, 2026: Grant of 91,659 unvested RSUs to Dr. Tan (vest in 16 quarterly installments).
  • Aug 20, 2026: Grant of 3,600 RSUs reported for Dr. Tan’s spouse (unvested; vesting schedule in footnotes).
  • Mar 19, 2026: 55,000 legacy Horizon stock options were exchanged for company options in connection with the closing of the business combination (exercise price $2.88; see footnotes).
• Shares owned after transaction: the filing does not state a consolidated “shares owned after” total for Dr. Tan in the summary table — ownership totals are not provided in this extract.
• Notable footnotes:
  • Each RSU converts to one Class A ordinary share upon vesting for no consideration (F2).
  • The Sept 12 settlement reflects cash settlement of part of the vested RSUs at the last reported share price on Sept 11, 2026 (F5).
  • Some grants/options reported relate to Dr. Tan’s spouse (F1, F6, F7, F8) and to legacy option exchanges from the March 19, 2026 business combination.
• Filing date: Form filed Sept 15, 2026; main transactions reported occurred on Sept 12, 2026.

Context

• RSU vesting and cash settlement: When RSUs vest, companies often either issue shares or settle an amount in cash to cover taxes or per plan terms; this filing shows a partial cash settlement (2,991 RSUs) at $15.22/share rather than an open‑market sale. That is common and does not necessarily indicate an active market sell decision.
• Options and legacy exchange: The March 19, 2026 entry reflects conversion/exchange of legacy options into company options with an exercise price of $2.88 and a formulaic share conversion (see footnotes). These are standard post‑combination adjustments and include both vested and unvested tranches.