Quick Takeaways
- SUMMIT PARTNERS L P has 5 issuer positions tracked on this page.
- Estimated disclosed ownership value: $822,355,176.
- Recent insider filing activity is available below.
- Info
- Portfolio
- Significant Ownership
- Insider Ownership
Insider Trading & Ownership of SUMMIT PARTNERS L P
- Location
- Boston, MA
- Summary
- The estimated value of insider holdings of SUMMIT PARTNERS L P is at least $822,355,176 dollars as of 05 Jan 2026. SUMMIT PARTNERS L P is the 10%+ Owner of EngageSmart, Inc. and owns shares of EngageSmart, Inc. stock worth about $572.61M. SUMMIT PARTNERS L P is the 10%+ Owner of LifeStance Health Group, Inc. and owns shares of LifeStance Health Group, Inc. (LFST) stock worth about $169.97M. SUMMIT PARTNERS L P is the 10%+ Owner of A10 Networks, Inc. and owns shares of A10 Networks, Inc. (ATEN) stock worth about $68.48M. SUMMIT PARTNERS L P is the 10%+ Owner of Solo Brands, Inc. and owns shares of Solo Brands, Inc. (SBDS) stock worth about $10.9M. SUMMIT PARTNERS L P is the 10%+ Owner of Klaviyo, Inc. and owns shares of Klaviyo, Inc. (KVYO) stock worth about $388.3K.
- Signature
- /s/ Adam H. Hennessey, as attorney-in-fact for Summit Partners, L.P.
- All Insider Reports
- All Insider Reports
Follow Filing Activity
Follow SUMMIT PARTNERS L P and return when a new Insider Trading filing appears.
This tracks SEC filing changes for this page using existing product update flows.
What Changed
- Largest disclosed position: EngageSmart, Inc. ($572,613,882).
- Past-year value change for that position: .
Why This Matters
- This page translates Forms 3/4/5 into a quick ownership context before you inspect each transaction row.
- You can cross-check role, issuer, and filing chronology directly against the SEC source.
Source Evidence
Filed on Form 4
See Original Filing
Insider ownership context is sourced from SEC Forms 3, 4, and 5.
Ownership of SUMMIT PARTNERS L P
| Symbol | Company | Relationship | Holdings Value | Past Year Net Change | Change % | Report Period |
|---|---|---|---|---|---|---|
| ESMT | EngageSmart, Inc. | 10%+ Owner | $572,613,882 | 07 Mar 2023 | ||
| LFST | LifeStance Health Group, Inc. | 10%+ Owner | $169,970,305 | -$42,626,750 | -20% | 18 Aug 2025 |
| ATEN | A10 Networks, Inc. | 10%+ Owner | $68,484,098 | 08 Sep 2022 | ||
| SBDS | Solo Brands, Inc. | 10%+ Owner | $10,898,613 | 01 Jan 2026 | ||
| KVYO | Klaviyo, Inc. | 10%+ Owner | $388,278 | -$617,204,750 | -100% | 08 Sep 2025 |
Insider Transactions Reported by SUMMIT PARTNERS L P:
| Sym | Company | Class | Transaction | % | Value $ | * Price $ | Shares | Shares After | Date | Ownership |
|---|
* An asterisk sign (*) next to the price indicates that the price is likely invalid.