Form
SCHEDULE 13G/A
Passive or exempt beneficial ownership filing.
SUMMIT PARTNERS L P - 30 Sep 2025 SCHEDULE 13G/A Report for Klaviyo, Inc. Series A Common Stock, par value $0.001 per share (KVYO)
- Filing manager
- SUMMIT PARTNERS L P
- Reporting owner
- Summit Partners, L.P.
- Beneficially owned shares
- 18,852,778 shares
- Large-stake signal
-
Ownership
12%Beneficial ownership of this reported class.
Shares
18,852,778 sharesShares beneficially owned as disclosed.
Event date
30 Sep 2025Date tied to the ownership event or amendment.
Accepted by SEC
13 Nov 2025EDGAR acceptance date.
How to read this large-stake filing
- Schedule 13D/G filings focus on beneficial ownership stakes, not a full portfolio.
- Compare this filing with the holder history and issuer page before treating the percentage as a current position.
- Use amendments to understand whether the disclosed stake increased, decreased, or changed reporting status.
- Class ownership
- 12%
- Symbol
- KVYO
- Shares outstanding
- 156,714,697 shares
- SEC form
- SCHEDULE 13G/A
- Accepted by SEC
- 13 Nov 2025, 16:05:02 UTC
- Event date
- 30 Sep 2025
- Prior SEC filing
- 08 Aug 2025
- Source filing
- View source filing
Ownership signal
CIK-linked ownership evidence from parsed SEC filings.
2 signals
Subject security
Names, identifiers, and filing context for this profile.
2 source fields
Source evidence
Original filing metadata and source links for verification.
5 source fields
Key filing fact
SUMMIT PARTNERS L P disclosed 12% ownership in Klaviyo, Inc. Series A Common Stock, par value $0.001 per share (KVYO) on 30 Sep 2025.
Key facts
- SUMMIT PARTNERS L P filed SCHEDULE 13G/A for Klaviyo, Inc. Series A Common Stock, par value $0.001 per share (KVYO).
- Disclosed ownership: 12%.
- Date of event: 30 Sep 2025.
Change
- Previous schedule filing date: 08 Aug 2025.
- Current filing was accepted on 13 Nov 2025, 16:05.
Research use
- This page turns one Schedule 13D/G filing into a quick large-stake read before the raw reporting-person rows.
- Use the linked SEC filing as the source of truth for ownership percentages, shares, and reporting-party details.
Evidence
Backed by Schedule 13D/13G
View source filing
Beneficial ownership values are sourced from the original SEC Schedule 13D/13G filing.
Reporting persons
Disclosed reporting parties (6)
Names, ownership percentages, voting power, signatures, titles, and CIKs as disclosed in this Schedule 13D/G filing.
| Name | Ownership | Shares owned | Sole voting power | Shared voting power | Signature | Title | CIK |
|---|---|---|---|---|---|---|---|
| Summit Partners Growth Equity Fund IX-A, L.P. | 7.1% | 11,142,414 | 0 | 11,142,414 | /s/ Adam H. Hennessey, as POA | Adam H. Hennessey, as Power of Attorney | |
| Summit Partners Growth Equity Fund IX-B, L.P. | 4.4% | 6,957,168 | 0 | 6,957,168 | /s/ Adam H. Hennessey, as POA | Adam H. Hennessey, as Power of Attorney | |
| Summit Partners Co-Invest (Kiwi), L.P. | 0.44% | 687,035 | 0 | 687,035 | /s/ Adam H. Hennessey, as POA | Adam H. Hennessey, as Power of Attorney | |
| Summit Investors GE IX/VC IV, LLC | 0.04% | 58,561 | 0 | 58,561 | /s/ Adam H. Hennessey, as POA | Adam H. Hennessey, as Power of Attorney | |
| Summit Investors GE IX/VC IV (UK), L.P. | 0.01% | 7,600 | 0 | 7,600 | /s/ Adam H. Hennessey, as POA | Adam H. Hennessey, as Power of Attorney | |
| Summit Partners, L.P. | 12% | 18,852,778 | 0 | 18,852,778 | /s/ Adam H. Hennessey, as POA | Adam H. Hennessey, as Power of Attorney |
CIK / CUSIP context first