O2 Investment Partners (www.o2investment.com) is pleased to announce that 4M Building Solutions (“4M”), a leading full-service commercial cleaning and janitorial services platform, has completed the acquisition of Mayfield, Kentucky based Bluegrass Commercial Cleaning (“Bluegrass”) and Elgin, Illinois based Rainbow Maintenance Services (“Rainbow”). Terms of the investment were not disclosed.

Husband and wife team Jared and Christy Baker purchased Bluegrass in 2015, and since then, the Bakers have grown the business into a trusted commercial cleaning leader across Kentucky. The Company specializes in janitorial services, strip/wax floors, and deep/disinfecting cleaning for clients in a variety of end markets including distribution, medical, banking, corporate owner occupied, government, and education.

Rainbow has been servicing the greater Chicago, IL metro area since 1985. The Company is a customer driven organization operating on a simple belief that quality workmanship and open communication are the keys to customer satisfaction. Rainbow brings with it long-tenured customers within an attractive and diverse set of end markets including distribution, corporate owner occupied, medical, and education.

Bluegrass and Rainbow mark 4M’s 15^th and 16^th acquisitions since partnering with O2 Investment Partners in January 2023. Leonard Carder, 4M CEO, said, “Both companies share a commitment to quality, customer service, and community values which aligns well with 4M's mission. We are honored to welcome their clients and Team Members into the 4M family as we continue our growth across the country. By bringing the full breadth of 4M’s resources to Bluegrass and Rainbow, we are excited to bring their customers greater operational support and service capacity. We look forward to building upon the strong foundation of both teams.”

Mark Heneman at O2 commented, “2026 has been a transformational year for 4M. We continue to improve our service quality and expand our commercial reach across the country. The two partnerships reflect that ongoing momentum, and we are excited to deepen our presence in both Kentucky and Illinois. We are thrilled to welcome Bluegrass, Rainbow, and their respective team members to the 4M platform.”

About Bluegrass Commercial Cleaning
Bluegrass Commercial Services is a provider of commercial janitorial services in Kentucky with a long-tenured customer base and a variety of end markets. Additional information is available at www.bluegrass-cleaning.com.

About Rainbow Maintenance Services
Rainbow Maintenance Services is a provider of commercial janitorial services in the greater Chicago, IL metro area with a long-tenured customer base and a variety of end markets. Additional information is available at www.rainbowms.com.

About 4M Building Solutions
Founded in 1978, 4M Building Solutions is a full-service cleaning, janitorial, housekeeping, and disinfection services company headquartered in St. Louis, Mo. The company’s operations span 27 Midwest, Northeast, Southeast, and Western states. More than 7,000 Team Members provide daily environmentally friendly cleaning to 220 million square feet of space in corporate owner-occupied facilities, multi-tenant office buildings, and facilities supporting industrial and manufacturing, logistics, distribution, education, healthcare, and senior living. Additional information is available at www.4-m.com.

About O2 Investment Partners
O2 Investment Partners is a Midwestern-based private equity firm that seeks to acquire majority interests in lower middle market niche services, technology, and select industrial companies. The firm invests in businesses with earnings growth potential and a clear path to the creation of shareholder value. O2 invests with a view toward partnering with management to build and grow the business and take it to its next stage of development. This requires not only a clear vision and strategic plan to create shareholder value, but a close partnership and alignment of interest with management. Additional information is available at www.o2investment.com.

View source version on businesswire.com: https://www.businesswire.com/news/home/20260721730180/en/

2026 has been a transformational year for 4M. We continue to improve our service quality and expand our commercial reach across the country.