[Form 4] Klaviyo, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Klaviyo, Inc. (KVYO) reported insider equity transactions by its President on Form 4. On 11/15/2025 and 11/17/2025, the officer converted 22,855 and 28,457 shares of Series B Common Stock into Series A Common Stock in connection with tax withholding obligations related to vesting and settlement of restricted stock units (RSUs.

The company withheld 34,326 shares of Series A Common Stock to cover taxes and the officer sold 7,104 Series A shares at a weighted average price of $27.39 per share under a Rule 10b5-1 trading plan adopted on November 22, 2024. Following these transactions, the officer beneficially owned 441,398 Series A shares (including vested and unvested RSUs) and 359,184 unvested RSUs tied to Series B Common Stock.

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
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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)
11/15/2025

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	11/15/2025		C(1)		22,855	A	(2)	454,371	D
Series A Common Stock	11/15/2025		F(3)		34,326	D	$28.61	420,045	D
Series A Common Stock	11/17/2025		C		28,457	A	(2)	448,502	D
Series A Common Stock	11/17/2025		S(4)		7,104	D	$27.39(5)	441,398(6)	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
Series B Common Stock	(2)	11/15/2025		C(1)			22,855	(2)	(2)	Series A Common Stock	22,855	$0	387,641	D
Series B Common Stock	(2)	11/17/2025		C			28,457	(2)	(2)	Series A Common Stock	28,457	$0	359,184(7)	D

Explanation of Responses:

1. Represents 22,855 shares of the Issuer's Series B Common Stock, par value $0.001 per share ("Series B Common Stock"), automatically converted into shares of the Issuer's Series A Common Stock, par value $0.001 per share ("Series A Common Stock"), in connection with tax withholding obligations related to the vesting and settlement of restricted stock units ("RSUs").

2. Each share of Series B Common Stock is convertible at any time at the option of the holder into one share of 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.

3. Represents shares of Series A Common Stock withheld by the Issuer to satisfy tax withholding obligations in connection with the vesting and settlement of RSUs.

4. 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.

5. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $26.96 to $27.86 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.

6. Consists of (i) 157,599 shares of Series A Common Stock and (ii) 283,799 unvested RSUs 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.

7. Consists of 359,184 unvested RSUs awarded under the Issuer's 2015 Stock Incentive Plan, each representing the contingent right to receive one share of Series B Common Stock upon vesting and settlement.

Remarks:

	/s/ Landon Edmond, Attorney-in-Fact	11/18/2025
	** 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 Klaviyo (KVYO) report on this Form 4?

The filing reports that the President of Klaviyo, Inc. (KVYO) converted Series B Common Stock into Series A Common Stock, had shares withheld to cover tax obligations related to RSU vesting, and sold a portion of Series A shares pursuant to a Rule 10b5-1 trading plan.

How many Klaviyo (KVYO) shares were sold and at what price?

The officer sold 7,104 shares of Klaviyo Series A Common Stock at a weighted average price of $27.39 per share, with individual sale prices ranging from $26.96 to $27.86 per share.

How many Klaviyo (KVYO) shares were converted from Series B to Series A?

On 11/15/2025, 22,855 shares of Series B Common Stock were converted into Series A Common Stock, and on 11/17/2025, an additional 28,457 Series B shares were converted into Series A shares.

Were the Klaviyo (KVYO) insider transactions under a Rule 10b5-1 plan?

Yes. The sale transactions were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on November 22, 2024.

How many Klaviyo (KVYO) shares does the officer beneficially own after these transactions?

After the reported transactions, the officer beneficially owned 441,398 shares related to Series A Common Stock, consisting of 157,599 actual Series A shares and 283,799 unvested RSUs, plus 359,184 unvested RSUs linked to Series B Common Stock.

Why were some Klaviyo (KVYO) shares withheld instead of sold for cash?

The filing states that 34,326 Series A shares were withheld by Klaviyo to satisfy tax withholding obligations arising from the vesting and settlement of RSUs, rather than being sold in the market.

What is the conversion feature of Klaviyo (KVYO) Series B Common Stock?

Each share of Klaviyo Series B Common Stock is convertible at any time at the holder's option into one share of Series A Common Stock and will automatically convert into one Series A share upon certain events described in the company’s certificate of incorporation. The Series B stock has no expiration date.