SEC Form 4 · accession 0001872873-26-000006
Cytek Biosciences, Inc. · CTKB
Statement of changes in beneficial ownership, as filed. Original on EDGAR ↗
Reporting owner
Wenbin Jiang
Officer — PRESIDENT AND CEO · Director
Period of report
Aug 18, 2026
Accepted (ET)
Aug 20, 2026 · 4:35 pm EDT
Rule 10b5-1 plan
box not checked
Issuer CIK
0001831915
Table I — non-derivative securities
| Security | Date | Code | Shares | Price | A/D | Owned after | D/I | Nature of ownership |
|---|---|---|---|---|---|---|---|---|
| Common StockF1 | Aug 18, 2026 | M | 11,781 | — | A | 5,488,984 | D | |
| Common StockF2 | Aug 18, 2026 | F | 2,869 | $4.67 | D | 5,486,115 | D | |
| Common StockF1 | Aug 18, 2026 | M | 22,100 | — | A | 5,508,215 | D | |
| Common StockF2 | Aug 18, 2026 | F | 5,382 | $4.67 | D | 5,502,833 | D | |
| Common StockF1 | Aug 18, 2026 | M | 29,002 | — | A | 5,531,835 | D | |
| Common StockF2 | Aug 18, 2026 | F | 7,062 | $4.67 | D | 5,524,773 | D | |
| Common StockF1 | Aug 18, 2026 | M | 57,212 | — | A | 5,581,985 | D | |
| Common StockF2 | Aug 18, 2026 | F | 20,956 | $4.67 | D | 5,561,029 | D |
Table II — derivative securities
| Security | Conv. / exercise price | Date | Code | Shares | A/D | Exercisable | Expires | Underlying | Underlying shares | Owned after | D/I |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Restricted Stock UnitsF1,F3 | — | Aug 18, 2026 | M | 11,781 | D | — | — | Common Stock | 11,781 | 27,494 | D |
| Restricted Stock UnitsF1,F4 | — | Aug 18, 2026 | M | 22,100 | D | — | — | Common Stock | 22,100 | 139,973 | D |
| Restricted Stock UnitsF1,F5 | — | Aug 18, 2026 | M | 29,002 | D | — | — | Common Stock | 29,002 | 299,694 | D |
| Restricted Stock UnitsF1,F6 | — | Aug 18, 2026 | M | 57,212 | D | — | — | Common Stock | 57,212 | 820,054 | D |
Explanation of responses
- F1Each Restricted Stock Unit (the "RSU Award") represents a contingent right to receive one share of the Issuer's common stock.
- F2Represents the number of shares withheld by and surrendered to the Issuer on August 18, 2026 to satisfy tax withholding obligations that arose in connection with the vesting of the RSU Award.
- F3The shares underlying the RSU Award shall vest over 4 years, with 2/48 of the total shares underlying the RSU Award vesting on May 18, 2023 and each May 18 thereafter; 3/48 of the total shares underlying the RSU Award vesting on August 18, 2023 and each August 18 thereafter; 3/48 of the total shares underlying the RSU Award vesting on November 18, 2023 and each November 18 thereafter; and 4/48 of the total shares underlying the RSU Award vesting on March 10, 2024 and each March 10 thereafter.
- F4The shares underlying the RSU Award shall vest over 4 years, with 2/48 of the total shares underlying the RSU Award vesting on May 18, 2024 and each May 18 thereafter; 3/48 of the total shares underlying the RSU Award vesting on August 18, 2024 and each August 18 thereafter; 3/48 of the total shares underlying the RSU Award vesting on November 18, 2024 and each November 18 thereafter; and 4/48 of the total shares underlying the RSU Award vesting on March 10, 2025 and each March 10 thereafter.
- F5The shares underlying the RSU Award shall vest over 4 years, with 2/48 of the total shares underlying the RSU Award vesting on May 18, 2025 and each May 18 thereafter; 3/48 of the total shares underlying the RSU Award vesting on August 18, 2025 and each August 18 thereafter; 3/48 of the total shares underlying the RSU Award vesting on November 18, 2025 and each November 18 thereafter; and 4/48 of the total shares underlying the RSU Award vesting on March 10, 2026 and each March 10 thereafter.
- F6The shares underlying the RSU Award shall vest over 4 years, with 2/48 of the total shares underlying the RSU Award vesting on May 18, 2026 and each May 18 thereafter; 3/48 of the total shares underlying the RSU Award vesting on August 18, 2026 and each August 18 thereafter; 3/48 of the total shares underlying the RSU Award vesting on November 18, 2026 and each November 18 thereafter; and 4/48 of the total shares underlying the RSU Award vesting on March 10, 2027 and each March 10 thereafter.