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Cytek Biosciences (CTKB) director exercises 43,973 RSUs, granted options and RSUs

Filing Impact
(Neutral)
Filing Sentiment
(Neutral)
Form Type
4

Rhea-AI Filing Summary

Cytek Biosciences director Michael Holder reported equity compensation activity. He exercised 43,973 Restricted Stock Units into Common Stock, and following these transactions he holds 60,694 Common Stock shares directly. The filing shows no open‑market buys or sells.

Holder also received a grant of 18,261 director stock options with a $4.05 exercise price, expiring on June 10, 2036. In addition, he was granted 33,333 new RSUs. Both the new option grant and RSUs are scheduled to vest 100% on the earlier of June 10, 2027 or Cytek’s 2027 annual meeting of stockholders, if that meeting is held in June 2027.

Positive

  • None.

Negative

  • None.

Insights

Routine director equity exercise and new grants, no open‑market trades.

The filing for Cytek Biosciences shows director Michael Holder exercising 43,973 RSUs into Common Stock and receiving new option and RSU awards. These are standard board compensation mechanisms rather than discretionary stock purchases or sales.

Post‑exercise, Holder owns 60,694 Common Stock shares directly, and has 18,261 options at $4.05 plus 33,333 RSUs scheduled to vest in 2027. With no open‑market buying or selling, the transactions mainly update his equity position and align compensation with future company performance.

Insider Holder Michael
Role null
Type Security Shares Price Value
Grant/Award Restricted Stock Units 33,333 $0.00 --
Grant/Award Director Stock Option (right to buy) 18,261 $0.00 --
Exercise Restricted Stock Units 43,973 $0.00 --
Exercise Common Stock 43,973 $0.00 --
Holdings After Transaction: Restricted Stock Units — 33,333 shares (Direct, null); Director Stock Option (right to buy) — 18,261 shares (Direct, null); Common Stock — 60,694 shares (Direct, null)
Footnotes (1)
  1. Each Restricted Stock Unit (the "RSU Award") represents a contingent right to receive one share of the Issuer's common stock. 100% of the shares subject to the RSU Award shall vest on the earlier of June 10, 2027 and the date of the Issuer's 2027 annual meeting of stockholders (provided such meeting is held in June 2027). 100% of the shares subject to the option shall vest on the earlier of June 10, 2027 and the date of the Issuer's 2027 annual meeting of stockholders (provided such meeting is held in June 2027). 100% of the shares subject to the RSU Award vested on June 10, 2026.
RSUs exercised 43,973 shares Restricted Stock Units converted into Common Stock on June 10, 2026
Shares owned after transactions 60,694 shares Common Stock directly owned by Michael Holder following Form 4 transactions
New stock options granted 18,261 options at $4.05 Director stock option grant, exercise price $4.05, expires June 10, 2036
New RSUs granted 33,333 RSUs Restricted Stock Units granted, scheduled to vest by June 10, 2027
Option expiration June 10, 2036 Expiration date of 18,261 director stock options
Future vesting date June 10, 2027 Target vesting date for new option and RSU awards or 2027 annual meeting
Restricted Stock Unit financial
"Each Restricted Stock Unit (the "RSU Award") represents a contingent right to receive one share"
A restricted stock unit is a promise from a company to give an employee shares of stock after certain conditions are met, like staying with the company for a set amount of time. It’s like earning a bonus that turns into company stock once you’ve proven your commitment, making it a way to motivate and reward employees.
Director Stock Option financial
"Director Stock Option (right to buy) with an exercise price of 4.0500"
Exercise or conversion of derivative security financial
"transaction_code_description: Exercise or conversion of derivative security"
vest financial
"100% of the shares subject to the RSU Award shall vest on the earlier of June 10, 2027"
A vest is the process by which an employee earns the right to receive certain benefits or ownership interests, such as stock or retirement funds, over time. It’s similar to earning a reward gradually, ensuring that the benefit becomes fully yours only after a set period or meeting specific conditions. This makes it important for investors because it determines when they can actually claim or use those benefits.
annual meeting of stockholders financial
"the date of the Issuer's 2027 annual meeting of stockholders (provided such meeting is held in June 2027)"
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Form 4 Insider Transactions: What Each Field Means →
SEC Form 4
FORM 4UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940
OMB APPROVAL
OMB Number:3235-0287
Estimated average burden
hours per response:0.5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.
1. Name and Address of Reporting Person*
Holder Michael
(Last)(First)(Middle)
C/O CYTEK BIOSCIENCES, INC.
47215 LAKEVIEW BLVD.
(Street)
FREMONT CALIFORNIA 94538
(City)(State)(Zip)
UNITED STATES
(Country)		2. Issuer Name and Ticker or Trading Symbol
Cytek Biosciences, Inc. [ CTKB ] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
XDirector10% Owner
Officer (give title below)Other (specify below)
2a. Foreign Trading Symbol
3. Date of Earliest Transaction (Month/Day/Year)
06/10/2026		6. Individual or Joint/Group Filing (Check Applicable Line)
XForm filed by One Reporting Person
Form filed by More than One Reporting Person
4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year)2A. Deemed Execution Date, if any (Month/Day/Year)3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeVAmount(A) or (D)Price
Common Stock06/10/2026M43,973A(1)60,694D
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year)3A. Deemed Execution Date, if any (Month/Day/Year)4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 6. Date Exercisable and Expiration Date (Month/Day/Year)7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeV(A)(D)Date ExercisableExpiration DateTitleAmount or Number of Shares
Restricted Stock Units(1)06/10/2026A33,333 (2) (2)Common Stock33,333$033,333D
Director Stock Option (right to buy)$4.0506/10/2026A18,261 (3)06/10/2036Common Stock18,261$018,261D
Restricted Stock Units(1)06/10/2026M43,973 (4) (4)Common Stock43,973$00D
Explanation of Responses:
1. Each Restricted Stock Unit (the "RSU Award") represents a contingent right to receive one share of the Issuer's common stock.
2. 100% of the shares subject to the RSU Award shall vest on the earlier of June 10, 2027 and the date of the Issuer's 2027 annual meeting of stockholders (provided such meeting is held in June 2027).
3. 100% of the shares subject to the option shall vest on the earlier of June 10, 2027 and the date of the Issuer's 2027 annual meeting of stockholders (provided such meeting is held in June 2027).
4. 100% of the shares subject to the RSU Award vested on June 10, 2026.
/s/ Valerie Barnett, Attorney-in-Fact06/12/2026
** Signature of Reporting PersonDate
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

Source: View Original Filing on SEC EDGAR

FAQ

What did Cytek Biosciences (CTKB) director Michael Holder report in this Form 4?

Director Michael Holder reported exercising 43,973 Restricted Stock Units into Common Stock and receiving new equity awards. The filing records compensation-related activity only, with no open-market purchases or sales of Cytek Biosciences shares disclosed in these transactions.

How many Cytek Biosciences shares does Michael Holder own after these transactions?

After exercising 43,973 Restricted Stock Units, Michael Holder directly owns 60,694 shares of Cytek Biosciences Common Stock. This figure comes from the Form 4’s post-transaction holdings column and reflects only his direct ownership reported in this filing.

What new stock options were granted to Cytek Biosciences director Michael Holder?

Michael Holder received 18,261 director stock options to buy Cytek Biosciences Common Stock at an exercise price of $4.05 per share. These options expire on June 10, 2036 and vest in full on the earlier of June 10, 2027 or the company’s 2027 annual meeting.

What new RSU awards did Michael Holder receive from Cytek Biosciences (CTKB)?

Holder was granted 33,333 Restricted Stock Units linked to Cytek Biosciences Common Stock. These RSUs are scheduled to vest 100% on the earlier of June 10, 2027 and the company’s 2027 annual meeting of stockholders, assuming that meeting occurs in June 2027.

Did Michael Holder buy or sell Cytek Biosciences shares on the open market in this Form 4?

No open-market buy or sell transactions are reported. The Form 4 shows an exercise of 43,973 RSUs into Common Stock and grants of options and RSUs, all coded as compensation or derivative exercises, not as purchases or sales in the market.

When did Michael Holder’s prior RSU award in Cytek Biosciences fully vest?

A footnote explains that 100% of the shares subject to a prior RSU Award vested on June 10, 2026. The 43,973 RSUs exercised into Common Stock in this Form 4 relate to that fully vested RSU Award.