Glaukos (NYSE: GKOS) CDO reports 1,031-share sale and tax withholding

Filing Impact

(Moderate)

Filing Sentiment

(Negative)

Form Type

Rhea-AI Filing Summary

Glaukos Corp chief development officer Tomas Navratil reported a combination of tax withholding and open-market sales of company stock. On March 16, 2026, 958 shares of common stock were withheld to cover tax obligations tied to the vesting of previously granted restricted stock units.

On the same date, he sold a total of 1,031 common shares in open-market transactions at weighted average prices of $97.33, $98.21, and $99.05 per share, under a pre-arranged Rule 10b5-1 trading plan. Following these transactions, he directly beneficially owns 73,631 shares of Glaukos common stock, including 35,687 restricted stock units that have not yet vested or been delivered.

Insider Trade Summary

Net Seller: 1,031 shares ($101,078)

Net Sell 4 txns

Insider Navratil Tomas

Role CHIEF DEVELOPMENT OFFICER

Sold 1,031 shs ($101K)

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	958	$98.94	$95K
Sale	Common Stock	460	$97.33	$45K
Sale	Common Stock	299	$98.21	$29K
Sale	Common Stock	272	$99.05	$27K

Holdings After Transaction: Common Stock — 74,662 shares (Direct)

Footnotes (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 14, 2024. Includes 35,687 restricted stock units that have not yet vested or been delivered to the Reporting Person. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on March 12, 2026. This transaction was executed in multiple trades at prices ranging from $96.85 to $97.85. The price reported above reflects the weighted average price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected. This transaction was executed in multiple trades at prices ranging from $97.86 to $98.86. The price reported above reflects the weighted average price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected. This transaction was executed in multiple trades at prices ranging from $98.87 to $99.11. The price reported above reflects the weighted average price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.

Form 4 Insider Transactions: What Each Field Means →

03/19/2026 - 04:10 PM

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)
03/16/2026

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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	03/16/2026		F		958⁽¹⁾	D	$98.94	74,662⁽²⁾	D
Common Stock	03/16/2026		S⁽³⁾		460	D	$97.33⁽⁴⁾	74,202⁽²⁾	D
Common Stock	03/16/2026		S⁽³⁾		299	D	$98.21⁽⁵⁾	73,903⁽²⁾	D
Common Stock	03/16/2026		S⁽³⁾		272	D	$99.05⁽⁶⁾	73,631⁽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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)

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 14, 2024.

2. Includes 35,687 restricted stock units that have not yet vested or been delivered to the Reporting Person.

3. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on March 12, 2026.

4. This transaction was executed in multiple trades at prices ranging from $96.85 to $97.85. The price reported above reflects the weighted average price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.

5. This transaction was executed in multiple trades at prices ranging from $97.86 to $98.86. The price reported above reflects the weighted average price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.

6. This transaction was executed in multiple trades at prices ranging from $98.87 to $99.11. The price reported above reflects the weighted average price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.

	Diana Scherer, Attorney-in-Fact	03/19/2026
	** 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)

Source: View Original Filing on SEC EDGAR

FAQ

What insider transactions did GKOS executive Tomas Navratil report?

Tomas Navratil reported tax withholding and open-market sales of Glaukos (GKOS) shares. On March 16, 2026, 958 shares were withheld for taxes on vested RSUs, and 1,031 shares were sold in the open market under a pre-arranged Rule 10b5-1 trading plan.

How many GLAUKOS Corp (GKOS) shares did Tomas Navratil sell and at what prices?

Tomas Navratil sold 1,031 Glaukos (GKOS) common shares in three open-market transactions. The weighted average sale prices were $97.33, $98.21, and $99.05 per share, with each trade executed in multiple lots within specified price ranges described in the filing’s footnotes.

How many GLAUKOS Corp (GKOS) shares does Tomas Navratil own after this Form 4?

After these transactions, Tomas Navratil beneficially owns 73,631 Glaukos (GKOS) shares. This total includes 35,687 restricted stock units that have not yet vested or been delivered, so part of his reported holdings will convert into deliverable shares only as vesting conditions are met over time.

Was the GKOS insider sale by Tomas Navratil made under a Rule 10b5-1 plan?

Yes. The Form 4 states the reported Glaukos (GKOS) sales were executed under a Rule 10b5-1 trading plan. The plan was adopted on March 12, 2026, indicating the transactions were pre-arranged rather than discretionary trades timed in reaction to short-term market movements.

What do the 958 GKOS shares withheld for Tomas Navratil represent?

The 958 Glaukos (GKOS) shares represent stock withheld for tax obligations on vested restricted stock units. Instead of paying cash taxes, a portion of the delivered shares was retained by the issuer, a common mechanism that does not reflect an open-market sale decision by the executive.