Morgan Stanley (KVYO) discloses 14.5M Klaviyo Series A shares in 13G/A

Rhea-AI Filing Summary

Klaviyo, Inc. received an updated ownership disclosure showing that Morgan Stanley and certain of its units beneficially own 14,538,026 shares of Klaviyo Series A common stock, representing 10.5% of the class as of the event date of 12/31/2025. Morgan Stanley reports no sole voting or dispositive power over these shares, with 8,343,244 shares subject to shared voting power and all 14,538,026 shares subject to shared dispositive power.

The filing is on a Schedule 13G/A basis, with Morgan Stanley certifying that the securities were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control of Klaviyo. The disclosure also notes that it only reflects securities held by specified Morgan Stanley reporting units and excludes other units whose holdings are disaggregated under SEC guidance.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 1)

Klaviyo, Inc.

(Name of Issuer)

Series A Common Stock

(Title of Class of Securities)

49845K101

(CUSIP Number)

12/31/2025

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No. 49845K101

1

Names of Reporting Persons

Morgan Stanley

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 8,343,244.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 14,538,026.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

14,538,026.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

10.5 %

12

Type of Reporting Person (See Instructions)

HC, CO

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Klaviyo, Inc.
(b)	Address of issuer's principal executive offices: 125 SUMMER STREET FLOOR 6, BOSTON, MA, 02110
Item 2.
(a)	Name of person filing: Morgan Stanley
(b)	Address or principal business office or, if none, residence: 1585 Broadway, New York, NY 10036
(c)	Citizenship: Delaware
(d)	Title of class of securities: Series A Common Stock
(e)	CUSIP No.: 49845K101
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:
(k)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.	Ownership
(a)	Amount beneficially owned: See the response(s) to Item 9 on the attached cover page(s).
(b)	Percent of class: 10.5 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: See the response(s) to Item 5 on the attached cover page(s).
	(ii) Shared power to vote or to direct the vote: See the response(s) to Item 6 on the attached cover page(s).
	(iii) Sole power to dispose or to direct the disposition of: See the response(s) to Item 7 on the attached cover page(s).
	(iv) Shared power to dispose or to direct the disposition of: See the response(s) to Item 8 on the attached cover page(s).
Item 5.	Ownership of 5 Percent or Less of a Class.
	Not Applicable
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	Not Applicable
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	Not Applicable
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11. * In Accordance with the Securities and Exchange Commission Release No. 34-39538 (January 12, 1998) (the "Release"), this filing reflects the securities beneficially owned, or that may be deemed to be beneficially owned, by certain operating units (collectively, the "MS Reporting Units") of Morgan Stanley and its subsidiaries and affiliates (collectively, "MS"). This filing does not reflect securities, if any, beneficially owned by any operating units of MS whose ownership of securities is disaggregated from that of the MS Reporting Units in accordance with the Release.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Morgan Stanley

Signature:	Christopher O'Hara
Name/Title:	Authorized Signatory, Morgan Stanley
Date:	01/08/2026

FAQ

What did Morgan Stanley disclose about Klaviyo (KVYO) in this Schedule 13G/A?

Morgan Stanley disclosed that it and certain of its units beneficially own 14,538,026 shares of Klaviyo Series A common stock, reported on an amended Schedule 13G/A.

What percentage of Klaviyo (KVYO) does Morgan Stanley report owning?

Morgan Stanley reports beneficial ownership of 10.5% of Klaviyo’s Series A common stock based on the aggregate 14,538,026 shares it reports.

What voting and dispositive powers does Morgan Stanley report over Klaviyo (KVYO) shares?

Morgan Stanley reports 0 shares with sole voting power and 8,343,244 shares with shared voting power. It also reports 0 shares with sole dispositive power and 14,538,026 shares with shared dispositive power.

Is Morgan Stanley’s Klaviyo (KVYO) stake reported as a passive investment?

Yes. Morgan Stanley certifies that the Klaviyo securities were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control of the company.

What is the reported event date for Morgan Stanley’s ownership in Klaviyo (KVYO)?

The date of the event requiring the filing is reported as 12/31/2025.

Does the 13G/A cover all Morgan Stanley units holding Klaviyo (KVYO) stock?

No. The disclosure states it reflects securities beneficially owned by specified Morgan Stanley reporting units and does not include any holdings by other units whose ownership is disaggregated under SEC Release No. 34-39538.