[Form 4] Klaviyo, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Stephen Eric Rowland, President and officer of Klaviyo, Inc. (KVYO), reported voluntary sales of Series A common stock on 09/15/2025 under a Rule 10b5-1 trading plan adopted on 11/22/2024. The filing shows two disposal entries: 6,905 shares sold at a weighted-average price of $31.90 per share (transactions ranged $31.43–$32.27), and 200 shares sold at $31.24. After these sales the reported beneficial ownership is shown as 438,821 and 438,621 shares respectively. The filing discloses that the total reported holdings consist of 129,070 issued shares and 309,551 unvested restricted stock units convertible into common shares upon vesting.

Positive

• Sales executed under a Rule 10b5-1 plan, indicating the transactions were preplanned and intended to provide affirmative defense under insider trading rules
• Filing discloses composition of holdings (129,070 issued shares and 309,551 unvested RSUs), improving transparency about economic ownership

Negative

• Insider disposal of 7,105 shares by the company President, which investors may view as insider selling
• Weighted-average sale price disclosure only; detailed per-trade quantities by price are not listed in the filing (though the filer offers to provide them on request)

Insights

Securities Analyst

TL;DR: Insider sold a small portion of holdings via a pre-established 10b5-1 plan; transaction is routine and non-material to outstanding shares.

The reported disposals total 7,105 Series A shares executed on 09/15/2025 under a Rule 10b5-1 plan adopted on 11/22/2024. The seller is the company President, which is material to note for governance transparency, but the filing does not indicate any change in role or unexpected event. The sales were executed across multiple prices with a disclosed weighted-average price and the filer committed to provide breakdowns on request, which supports transparency. No derivative transactions or amendments are reported.

Corporate Governance Expert

TL;DR: Use of a 10b5-1 plan signals preplanned, compliant selling; the disclosure is routine but relevant to monitoring insider behavior.

The reporting person used a documented 10b5-1 trading plan, reducing the likelihood that these sales reflect undisclosed, company-specific developments. The filing clearly states the composition of remaining holdings (issued shares plus unvested RSUs), aiding assessment of true economic ownership. There is no indication of accelerated vesting, option exercises, or other atypical compensation events in this Form 4.

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).

X

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^*

Rowland Stephen Eric

(Last) (First) (Middle)

C/O KLAVIYO, INC.

125 SUMMER STREET, 6TH FLOOR

(Street)

BOSTON MA 02110

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Klaviyo, Inc. [ KVYO ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	President

3. Date of Earliest Transaction (Month/Day/Year)
09/15/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

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

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

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
Series A Common Stock	09/15/2025		S(1)		6,905	D	$31.9(2)	438,821	D
Series A Common Stock	09/15/2025		S(1)		200	D	$31.24	438,621(3)	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. These transactions were effected by the Reporting Person pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 22, 2024.

2. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $31.43 to $32.27 per share. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

3. Consists of (i) 129,070 shares of the Issuer's Series A Common Stock, par value $0.001 per share ("Series A Common Stock"), and (ii) 309,551 unvested restricted stock units awarded under the Issuer's 2023 Stock Option and Incentive Plan, each representing the contingent right to receive one share of Series A Common Stock upon vesting and settlement.

Remarks:

	/s/ Landon Edmond, Attorney-in-Fact	09/17/2025
	** 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.

FAQ

What insider transactions did KVYO President Stephen Eric Rowland report on Form 4?

The filing reports disposals of 6,905 shares at a weighted-average price of $31.90 and 200 shares at $31.24, both dated 09/15/2025.

Were the sales by the KVYO insider part of a pre-established trading plan?

Yes. The transactions were effected pursuant to a Rule 10b5-1 trading plan adopted on 11/22/2024.

How many Klaviyo shares does the reporting person beneficially own after these transactions?

The Form 4 shows beneficial ownership of 438,821 and 438,621 shares following the reported transactions on separate lines.

Does the filing disclose restricted stock units or unvested awards for the reporting person?

Yes. The reported holdings include 309,551 unvested restricted stock units and 129,070 issued Series A shares.

Does the Form 4 show any derivative transactions or option exercises for this reporting person?

No. Table II for derivative securities contains no reported transactions in this filing.