Lower middle market private equity firm
Keystone Capital
- HeadquartersChicago, IL S1
- Founded1994 S2
- Websitekeystonecapital.com
- Last verifiedOctober 20, 2026
At a glance
| Latest fund | Keystone Fund III, $630M (Feb 2024) S6 |
|---|---|
| EBITDA range | $5M to $20M S1 |
| Deal types | Platform, Add-on S5 |
| Geography | North America S6 |
| Sectors | IT Services & MSP, Accounting & Professional Services, Consumer & Food, Distribution, Dental |
What Keystone Capital buys
Keystone Capital is a Chicago investor that has been buying companies since 1994. For more than 25 years it used only its own partners' money; it took outside investors in 2021 and has since raised two funds with more than $1 billion of commitments, with its own team still the largest investor in both. It targets companies with $5 million to $20 million of EBITDA in six areas: commercial and industrial services (facility services, testing and inspection, repair and maintenance), food and beverage, industrial technology, professional and tech-enabled services (including IT consulting and managed services), technical and engineering services, and healthcare services.
Keystone backs existing management, often with owners keeping a real stake, then grows each platform through add-ons: VDA made more than 20 acquisitions and Integra Testing Services nearly 20 under its ownership. It says it sets no fixed holding period and can often close within 30 days. A smaller business is most likely to meet Keystone as an add-on, as when Gillson Sciences bought SanAir and Asbestos Identification Laboratory in 2026.
Recent deals
Announced in the 24 months before October 20, 2026.
| Date | Company | Type | Sector | Source |
|---|---|---|---|---|
| Oct 2026 | VDAElevator and escalator inspection and consulting firm, held since 2021, sold to Warren Equity Partners | Exit | Source | |
| Jul 2026 | Endure Critical SolutionsNew critical power and battery service platform built from Quality Power Solutions and Power Storage Solutions; both leadership teams kept significant ownership | Platform | Source | |
| Jul 2026 | Integra Testing ServicesCommercial HVAC testing and balancing platform, built with nearly 20 acquisitions since 2021, sold to Harvest Partners | Exit | HVAC, Plumbing & Electrical | Source |
| May 2026 | Asbestos Identification LaboratoryBoston-area testing laboratory added to Gillson Sciences | Add-on | Source | |
| Feb 2026 | SanAir Technologies LaboratoryRichmond, Virginia environmental and industrial hygiene testing lab added to Gillson Sciences | Add-on | Source | |
| Nov 2025 | Chartwell Financial AdvisoryMinneapolis valuation and corporate finance advisory firm; management shareholders kept a significant stake | Platform | Accounting & Professional Services | Source |
| Oct 2025 | Inspire11Digital transformation and technology consultancy, held about five years, sold to Insight Enterprises | Exit | IT Services & MSP | Source |
| Aug 2025 | Gillson SciencesLaboratory testing platform formed from Azzur Labs and Micro Measurement Laboratories | Platform | Source | |
| May 2025 | Penta Fine IngredientsNew Jersey supplier of specialty chemicals and ingredients for flavor, fragrance and pharmaceutical makers | Platform | Source | |
| March 2025 | StartKleenRecapitalization of a food plant sanitation services company with management and KCM Capital Partners; the founder still leads it | Platform | Source |
Portfolio by sector
From the firm's portfolio page S4.
Commercial & Industrial Services
- Endure Critical Solutions
- Identiti
- KENDELL
- Precision Point Metrics
- StartKleen
Commercial & Industrial Services; Healthcare Services
- Gillson Sciences
Food & Beverage
- Baily International
- Best Foods
- Om Trading
- Penta Fine Ingredients
- Tribute
Healthcare Services
- Merge
Professional and Technology-Enabled Services
- BarkleyOKRP
- Chartwell Financial Advisory
- Novatio
Technical Services
- ClearWater Solutions
- Paslay Group
- Pinchin
Other
- Cherry Hill Programs
- Foundation Dental Partners
- Scott Group Studio
Greymont’s take
How Keystone Capital fits a seller
Keystone suits founders of service, food and niche professional firms with $5 million to $20 million of EBITDA who want a patient owner and expect to keep running the company. It says it does not tell owners how to run their businesses and leaves strategic direction to management, and in recent deals such as Chartwell Financial Advisory and Endure Critical Solutions the existing owners kept a significant stake.
A sale to Keystone is usually the start of a buy-and-build. It grows platforms through many add-ons and then sells them, often to larger private equity firms, as it did with Integra to Harvest Partners and VDA to Warren Equity Partners in 2026, four to five years after each first investment. Owners rolling equity should ask how long Keystone really expects to hold, given its claim of no fixed timeline, and how much of the add-on plan they will lead.
Questions owners ask
What size company does Keystone Capital target?
Its homepage gives a target of $5 million to $20 million of EBITDA. It invests mainly in North American businesses, and its Fund III closed at a $630 million hard cap in February 2024.
Does Keystone invest in IT services firms?
Yes. IT consulting, managed services and process automation are on its list of interests. It currently owns Novatio, an automation consultancy, and sold Inspire11, a digital transformation consultancy, to Insight Enterprises in October 2025.
Do owners keep a stake when Keystone invests?
Often. When Keystone formed Endure Critical Solutions in July 2026, the leaders of both founding companies kept significant ownership, and Chartwell Financial Advisory's management shareholders did the same in November 2025.
How quickly can Keystone close a deal?
Keystone says its small size and long-standing lender relationships let it move fast, and that it can often complete a purchase within 30 days, at the value it first commits to.
Sources
- S1Keystone Capital home page Accessed October 20, 2026
- S2Keystone Capital: About (history and areas of interest) Accessed October 20, 2026
- S3Keystone Capital: Approach Accessed October 20, 2026
- S4Keystone Capital: Portfolio (active filter) Accessed October 20, 2026
- S5Keystone Capital: Media Center Accessed October 20, 2026
- S6Keystone Capital Closes Oversubscribed Fund III (February 1, 2024) Accessed October 20, 2026
- S7Keystone Capital Announces Formation of Endure Critical Solutions (July 1, 2026) Accessed October 20, 2026
- S8Keystone Capital Announces Partnership with Chartwell Financial Advisory (November 3, 2025) Accessed October 20, 2026
- S9Keystone Capital Announces Exit of VDA (October 5, 2026) Accessed October 20, 2026
- S10Keystone Capital Announces Exit of Integra Testing Services (July 1, 2026) Accessed October 20, 2026
Compiled by Greymont Advisors from public sources, including the firm’s own website and press releases. Greymont is not affiliated with Keystone Capital. Figures are as reported on the dates shown and may have changed. Request a correction