SUMMIT PARTNERS L P - 21 Aug 2025 Form 4 Insider Report for Klaviyo, Inc. (KVYO)

Role: 10%+ Owner
Signature: /s/ Adam Hennessey, as attorney-in-fact for Summit Partners, L.P.
Issuer symbol: KVYO
Transactions as of: 21 Aug 2025
Net transactions value: $0
Form type: 4
Filing time: 22 Aug 2025, 16:12:34 UTC
Previous filing: 20 Aug 2025
Next filing: 27 Aug 2025
SEC: View on sec.gov

Reporting Owners (3)

Name	Relationship	Address	Signature	Signature date	CIK
SUMMIT PARTNERS L P	10%+ Owner	222 BERKELEY STREET, 18TH FLOOR, BOSTON	/s/ Adam Hennessey, as attorney-in-fact for Summit Partners, L.P.	22 Aug 2025	0000830588
Summit Partners Growth Equity Fund IX-A, L.P.	10%+ Owner	222 BERKELEY STREET, 18TH FLOOR, BOSTON	/s/ Adam Hennessey, as attorney-in-fact for Summit Partners Growth Equity Fund IX-A, L.P.	22 Aug 2025	0001634415
Summit Partners Growth Equity Fund IX-B, L.P.	10%+ Owner	222 BERKELEY STREET, 18TH FLOOR, BOSTON	/s/ Adam Hennessey, as attorney-in-fact for Summit Partners Growth Equity Fund IX-B, L.P.	22 Aug 2025	0001634426

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	KVYO	Series A Common Stock, par value $0.001 per share	Other	$0	-500,000	-100%	$0.000000	0	21 Aug 2025	See footnote	F1, F2

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	Represents a distribution of 307,809 shares of Series A common stock, par value $0.001 per share ("Series A Common Stock") held by Summit Partners Growth Equity Fund IX-A, L.P. ("Fund IX-A") and 192,191 shares of Series A Common Stock held by Summit Partners Growth Equity Fund IX-B, L.P. ("Fund IX-B"), in each case to facilitate bona fide charitable gifts.
F2	Summit Partners, L.P. is the manager of Summit Partners GE IX, LLC, which is the general partner of Summit Partners GE IX, LP, which is the general partner of Fund IX-A and Fund IX-B. The investment committee of Summit Partners, L.P., is currently composed of Peter Y. Chung, Scott C. Collins, and Peter L. Rottier, who may be deemed to have voting and dispositive authority over, and therefore beneficial ownership of, the reported securities. Each of the foregoing entities, Mr. Chung, Mr. Collins, and Mr. Rottier disclaims beneficial ownership of the shares, except to the extent of such person's or entity's pecuniary interest therein and the filing of this statement shall not be deemed an admission that any of the foregoing entities or persons are, for purposes of Section 16 of the Act or otherwise, the beneficial owner of any equity securities covered by this statement.

Content

Represents a distribution of 307,809 shares of Series A common stock, par value $0.001 per share ("Series A Common Stock") held by Summit Partners Growth Equity Fund IX-A, L.P. ("Fund IX-A") and 192,191 shares of Series A Common Stock held by Summit Partners Growth Equity Fund IX-B, L.P. ("Fund IX-B"), in each case to facilitate bona fide charitable gifts.

Summit Partners, L.P. is the manager of Summit Partners GE IX, LLC, which is the general partner of Summit Partners GE IX, LP, which is the general partner of Fund IX-A and Fund IX-B. The investment committee of Summit Partners, L.P., is currently composed of Peter Y. Chung, Scott C. Collins, and Peter L. Rottier, who may be deemed to have voting and dispositive authority over, and therefore beneficial ownership of, the reported securities. Each of the foregoing entities, Mr. Chung, Mr. Collins, and Mr. Rottier disclaims beneficial ownership of the shares, except to the extent of such person's or entity's pecuniary interest therein and the filing of this statement shall not be deemed an admission that any of the foregoing entities or persons are, for purposes of Section 16 of the Act or otherwise, the beneficial owner of any equity securities covered by this statement.