Significant Ownership of SUMMIT PARTNERS L P

Large-stake snapshot 1 signal
Large-stake filing summary
  • Recent SEC Schedule 13D/G filings for SUMMIT PARTNERS L P focus on large-stake beneficial ownership disclosures and amendments.
  • Use this view to spot new large holders, amended positions, and activist-style ownership evidence.
Manager Names, identifiers, and filing context for this profile. 2 identity fields
Manager location
Boston, MA
Manager signature
By: Summit Master Company, LLC / /s/ Adam H. Hennessey, as POA - Its: General Partner / Adam H. Hennessey, as Power of Attorney

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Significant Ownership of SUMMIT PARTNERS L P

Sym Company Class Ownership Holdings Value Net Change Nb Shares Change % Reporting Name Report Period
KVYO Klaviyo, Inc. Series A Common Stock, par value $0.001 per share 12% $522,033,423 -$331,587,750 18,852,778 -39% Summit Partners, L.P. 30 Sep 2025
LFST LifeStance Health Group, Inc. Common Stock, par value $0.01 per share 7.5% $186,066,273 -$27,486,161 29,209,776 -13% Summit Partners, L.P. 31 Mar 2026

Schedules 13D/G Reported by SUMMIT PARTNERS L P:

Sym Target Class Ownership Change Current shares Change Value Reporting name Form Report period Filing date
Schedule rows are parsed from SEC 13D/G filings. Open the linked filing or target page to verify the reported ownership and shares.
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