McCombe William D. 4

What Happened

• William D. McCombe, Chief Financial Officer of Cytek Biosciences (CTKB), was granted two restricted stock unit (RSU) awards on March 10, 2026 (136,205 RSUs and 256,790 RSUs, total 392,995 RSUs). On the same date, portions of RSUs converted/settled into common shares (6,320 and 17,401 shares).
• Of the converted shares (23,721 total), 9,748 shares were withheld/surrendered to the company to satisfy tax withholding obligations at $4.23 per share, totaling $41,234. That leaves a net of 13,973 shares delivered to McCombe after withholding.
• These were awards and vesting/conversion events (not open-market buys or sales). The filing shows grant and derivative conversion activity plus the routine tax-withholding disposition.

Key Details

• Transaction date: March 10, 2026; Form 4 filed March 12, 2026 (appears filed within the usual two-business-day window).
• Grants: 136,205 RSUs and 256,790 RSUs granted (derivative awards, $0 per share reported).
• Conversions: 6,320 and 17,401 RSUs converted into common stock (total 23,721).
• Tax withholding: 2,603 and 7,145 shares withheld (total 9,748) at $4.23/share; withheld shares valued at $11,011 and $30,223 respectively (total $41,234).
• Net shares received after withholding: 13,973 (23,721 converted − 9,748 withheld).
• Shares owned following the transactions: not specified in the provided filing data.
• Footnotes: RSUs represent contingent rights to receive one share each (F1). Withheld shares were surrendered to the issuer to satisfy tax obligations on vesting (F2). Vesting schedules for the awards/options are detailed in the filing (F3–F6).

Context

• This was primarily an award/vesting and conversion event; the withholding is a routine tax-related disposition (code F). For retail investors, awards and vesting are common executive compensation events and do not necessarily signal buying or selling intent. The filing includes both the grant of RSUs and their partial conversion/settlement with shares withheld for taxes.