Hallen Ed - 11 Sep 2025 Form 4 Insider Report for Klaviyo, Inc. (KVYO)

Role: Director, 10%+ Owner
Signature: /s/ Landon Edmond, Attorney-in-Fact
Issuer symbol: KVYO
Transactions as of: 11 Sep 2025
Net transactions value: $0
Form type: 4
Filing time: 12 Sep 2025, 18:08:57 UTC
Previous filing: 20 Sep 2023
Next filing: 17 Sep 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Hallen Ed	Director, 10%+ Owner	C/O KLAVIYO, INC. 125 SUMMER STREET, 6TH FLOOR, BOSTON	/s/ Landon Edmond, Attorney-in-Fact	12 Sep 2025	0001991125

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	KVYO	Series A Common Stock	Conversion of derivative security		+990,000			990,000	11 Sep 2025	Direct	F1
transaction	KVYO	Series A Common Stock	Gift	$0	-990,000	-100%	$0.000000	0	11 Sep 2025	Direct	F2
transaction	KVYO	Series A Common Stock	Gift	$0	+200,000		$0.000000	200,000	11 Sep 2025	By Hodgkins Trust	F2, F3
transaction	KVYO	Series A Common Stock	Gift	$0	+790,000		$0.000000	790,000	11 Sep 2025	By Hodgkins LLC	F2, F4

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	KVYO	Series B Common Stock	Conversion of derivative security	$0	-990,000	-3%	$0.000000	31,999,106	11 Sep 2025	Series A Common Stock	990,000		Direct	F1

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

Explanation of Responses:

Id	Content
F1	Each share of the Issuer's Series B Common Stock, par value $0.001 per share ("Series B Common Stock"), is convertible at any time at the option of the holder into one share of the Issuer's Series A Common Stock, par value $0.001 per share ("Series A Common Stock"), and will automatically convert into one share of Series A Common Stock upon the occurrence of certain events as set forth in the Issuer's certificate of incorporation. The Series B Common Stock has no expiration date.
F2	On September 11, 2025, the Reporting Person transferred 200,000 shares of Series A Common Stock to Hodgkins Trust and 790,000 shares of Series A Common Stock to Hodgkins LLC for estate planning purposes, in each case for no consideration.
F3	Shares are owned directly by Hodgkins Trust for the benefit of the Reporting Person and the Reporting Person's family, and of which the trustee is an independent institution. The Reporting Person disclaims Section 16 beneficial ownership of such shares except to the extent of his pecuniary interest therein, if any, and this report shall not be deemed to be an admission that he has beneficial ownership of such shares for Section 16 or any other purpose.
F4	Shares held by Hodgkins LLC, of which the Reporting Person serves as manager. The Reporting Person disclaims Section 16 beneficial ownership of such shares except to the extent of his pecuniary interest therein, if any, and this report shall not be deemed to be an admission that he has beneficial ownership of such shares for Section 16 or any other purpose.