GLAUKOS (GKOS) CDO has 5,798 shares withheld to cover RSU tax

Rhea-AI Filing Summary

GLAUKOS Corp Chief Development Officer Tomas Navratil reported a routine tax-withholding share disposition tied to restricted stock unit vesting. On March 31, 2026, 5,798 shares of common stock were withheld by the company at $109.60 per share to cover his tax obligations when RSUs granted on March 22, 2023 vested and were delivered. Following this withholding, he directly holds 95,440 shares, which includes 45,793 restricted stock units that are granted but have not yet vested or been delivered.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Navratil Tomas

Role CHIEF DEVELOPMENT OFFICER

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	5,798	$109.60	$635K

Holdings After Transaction: Common Stock — 95,440 shares (Direct)

Footnotes (1)

1. Consists of shares withheld by the Issuer with respect to tax withholding obligations of the Reporting Person upon vesting and delivery of shares of common stock underlying restricted stock units previously granted by the Issuer on March 22, 2023. Includes 45,793 restricted stock units that have not yet vested or been delivered to the Reporting Person.

Key Figures

Shares withheld for taxes: 5,798 shares Withholding price: $109.60 per share Shares held after transaction: 95,440 shares +2 more

5 metrics

Shares withheld for taxes 5,798 shares Withheld on March 31, 2026 for RSU tax obligations

Withholding price $109.60 per share Value used for tax-withholding disposition

Shares held after transaction 95,440 shares Direct holdings following tax-withholding disposition

Unvested restricted stock units 45,793 RSUs Granted but not yet vested or delivered

Transaction code F Payment of tax liability by delivering securities

Key Terms

restricted stock units, tax withholding obligations, vesting and delivery, transaction code F

4 terms

restricted stock units financial

"delivery of shares of common stock underlying restricted stock units previously granted"

Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.

tax withholding obligations financial

"shares withheld by the Issuer with respect to tax withholding obligations of the Reporting Person"

vesting and delivery financial

"upon vesting and delivery of shares of common stock underlying restricted stock units"

transaction code F regulatory

"transaction_code_description: Payment of exercise price or tax liability by delivering securities"

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED 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^*

Navratil Tomas

(Last) (First) (Middle)

C/O GLAUKOS CORPORATION

ONE GLAUKOS WAY

(Street)

ALISO VIEJO CALIFORNIA 92656

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
GLAUKOS Corp [ GKOS ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	CHIEF DEVELOPMENT OFFICER

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
03/31/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form 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)
			Code	V	Amount	(A) or (D)	Price
Common Stock	03/31/2026		F		5,798(1)	D	$109.6	95,440(2)	D

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)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Consists of shares withheld by the Issuer with respect to tax withholding obligations of the Reporting Person upon vesting and delivery of shares of common stock underlying restricted stock units previously granted by the Issuer on March 22, 2023.

2. Includes 45,793 restricted stock units that have not yet vested or been delivered to the Reporting Person.

	Diana Scherer, Attorney-in-Fact	04/02/2026
	** Signature of Reporting Person	Date
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)

FAQ

What did GLAUKOS (GKOS) executive Tomas Navratil report in this Form 4?

Tomas Navratil reported a share disposition related to tax withholding, not an open-market trade. The company withheld 5,798 shares of GLAUKOS common stock when previously granted restricted stock units vested and were delivered to him.

How many GLAUKOS (GKOS) shares were withheld for Tomas Navratil’s taxes?

The company withheld 5,798 shares of GLAUKOS common stock at $109.60 per share. These shares covered Tomas Navratil’s tax withholding obligations triggered by the vesting and delivery of previously granted restricted stock units.

Was Tomas Navratil’s GLAUKOS (GKOS) Form 4 a sale on the open market?

No, the transaction was not an open-market sale. It was a tax-withholding disposition, where GLAUKOS retained 5,798 shares to satisfy Tomas Navratil’s tax obligations upon vesting of restricted stock units granted on March 22, 2023.

How many GLAUKOS (GKOS) shares does Tomas Navratil hold after this transaction?

After the tax-withholding disposition, Tomas Navratil directly holds 95,440 GLAUKOS shares. This figure includes restricted stock units, of which 45,793 have been granted but have not yet vested or been delivered to him.

What does transaction code F mean in Tomas Navratil’s GLAUKOS (GKOS) Form 4?

Transaction code F indicates a payment of exercise price or tax liability using securities. In this case, it reflects shares of GLAUKOS common stock withheld by the company to cover Tomas Navratil’s tax obligations when restricted stock units vested.

What RSU grant is referenced in Tomas Navratil’s GLAUKOS (GKOS) filing?

The filing references restricted stock units granted to Tomas Navratil on March 22, 2023. Shares were withheld upon vesting and delivery, and 45,793 restricted stock units from his awards have not yet vested or been delivered.