Lower middle market private equity and junior capital investor
Rock Island Capital
- HeadquartersOak Brook, IL S1
- Websiterockislandcapital.com
- Last verifiedNovember 3, 2026
At a glance
| Revenue range | Up to $250M S2 |
|---|---|
| Deal types | Platform, Minority, Growth S4 |
| Geography | United States, Canada S2 |
| Sectors | Industrial & Manufacturing, Distribution, Construction Services, HVAC, Plumbing & Electrical |
What Rock Island Capital buys
Rock Island Capital is an Oak Brook, Illinois firm that has raised more than $550 million of committed capital to invest in established manufacturing, distribution and service companies in the United States and Canada. Its limits are revenue of up to $250 million and enterprise value of up to $150 million. It can take a majority or a minority stake and can invest through common stock, preferred stock or mezzanine debt, so a deal can be shaped around what the owner needs. It generally avoids turnarounds and early-stage companies.
Most of its deals are recapitalizations done with management, where a founder or family sells part or all of the company and the managers become owners. It also funds management buyouts, generational ownership changes, and growth or acquisition plans. Current holdings range from fastener, blade and lighting makers to a Tulsa commercial HVAC contractor, a Chicago-area aerial lift rental company and a steel service center group. In 2026 it co-invested in Grady Bay Capital's recapitalization of BrickHouse GPS.
Recent deals
Announced in the 24 months before November 3, 2026.
| Date | Company | Type | Sector | Source |
|---|---|---|---|---|
| Jun 2026 | BrickHouse GPSCo-investor in Grady Bay Capital's recapitalization of the Indianapolis GPS tracking and fleet telematics company | Investment | Software & SaaS | Source |
| 2025 | RP RentsRecapitalization with management of an aerial lift and equipment rental company serving Chicagoland, Northwest Indiana and Southern Wisconsin | Platform | Construction Services | Source |
| 2025 | Belle Aire CreationsLibertyville, Illinois fragrance and odor control compound maker sold to Givaudan | Exit | Industrial & Manufacturing | Source |
| 2025 | Excel EngineeringIowa engine durability and emissions testing company sold to a private equity firm | Exit | Source |
Portfolio by sector
From the firm's portfolio page S5.
Bread and bun slicing blade manufacturer
- Hansaloy
Commercial and industrial facility services
- Exposed Surfaces
Concrete polishing products distributor
- Runyon Surface Prep
Equipment rental, parts and service
- RP Rents
GPS tracking and fleet telematics
- BrickHouse GPS
Industrial equipment distributor and service provider
- Central Power
Industrial fastener manufacturer
- Valley Fastener Group
Laser cutting and metal fabrication
- ALZA Group
LED high bay lighting manufacturer
- LUX Dynamics
Mechanical and HVAC services
- Oklahoma Chiller
Nonwoven materials converter and distributor
- Superior Felt & Filtration
Organic animal feed manufacturer
- Scratch and Peck
Steel service center
- Esmark
Past investments: Belle Aire Creations, Excel Engineering
Greymont’s take
How Rock Island Capital fits a seller
Rock Island suits owners of steady, profitable industrial, distribution or service businesses who want liquidity but are not ready to step away. Its recapitalizations usually make management part owners, and the firm says owners of closely held companies can keep significant ownership and day-to-day control. That makes it a natural fit for a family business planning a handoff to the next generation or buying out a passive partner.
Because it can invest through preferred stock or mezzanine debt as well as common equity, a Rock Island deal may not look like a standard buyout. Owners should ask exactly what security the firm would hold, what control rights come with it, and how long it expects to stay. Its holding periods vary: it still owns Central Power from 2015, while recent exits went to a global strategic (Givaudan bought Belle Aire) and to another private equity firm (Excel Engineering).
Questions owners ask
How big a company will Rock Island invest in?
Its criteria call for revenue of up to $250 million and an enterprise value of up to $150 million, with the business based in the United States or Canada.
Can an owner keep a stake after Rock Island invests?
Yes. It describes its recapitalizations as giving owners liquidity while they keep significant ownership and day-to-day control, and its portfolio pages show most deals done together with management.
What kinds of companies does Rock Island own today?
Its 13 active investments include manufacturers such as Valley Fastener Group and Hansaloy, distributors such as Central Power and Runyon Surface Prep, and service companies such as Oklahoma Chiller, Exposed Surfaces and RP Rents.
Sources
- S1Rock Island Capital home page (Oak Brook address, committed capital, active investments) Accessed November 3, 2026
- S2Rock Island Capital: Investment Criteria Accessed November 3, 2026
- S3Rock Island Capital: Private Capital Accessed November 3, 2026
- S4Rock Island Capital: Types of Investments Accessed November 3, 2026
- S5Rock Island Capital: Portfolio (active and realized investments) Accessed November 3, 2026
- S6Rock Island Capital: BrickHouse GPS Accessed November 3, 2026
- S7Grady Bay Capital Completes Acquisition of Brickhouse GPS (PR.com, June 4, 2026) Accessed November 3, 2026
- S8Rock Island Capital: RP Rents Accessed November 3, 2026
- S9Rock Island Capital: Belle Aire Accessed November 3, 2026
- S10Rock Island Capital: Excel Engineering Accessed November 3, 2026
- S11Rock Island Capital: Central Power Accessed November 3, 2026
- S12Rock Island Capital: Oklahoma Chiller Accessed November 3, 2026
Compiled by Greymont Advisors from public sources, including the firm’s own website and press releases. Greymont is not affiliated with Rock Island Capital. Figures are as reported on the dates shown and may have changed. Request a correction