Protos Security and Southfield Capital Announce the Strategic Acquisition of Summit Off Duty Services

June 4, 2024

Share this article

GREENWICH, CT – Southfield Capital, a premier lower middle market private equity firm, announced today that Security Services Holdings LLC, (“Protos”), a tech-enabled vendor managed security services provider in North America, has completed the acquisition of Summit Off Duty Services (“Summit”), an off-duty police officer security provider. The acquisition of Summit represents Protos’ tenth acquisition since partnering with Southfield.
 
Headquartered in Irving, TX, Summit manages onsite security for clients nationwide, providing security and law enforcement industry expertise through a vast nationwide network of police officers. Summit’s suite of services and features provides access to more than 60,000 police officers, representing more than 1,400 law enforcement agencies.
 
Alex Smith, President of Summit said, “Our commitment to providing high quality security solutions aligned closely with Protos’ mission, making the partnership a favorable path for Summit. I am confident that Protos and Summit will continue to drive success and improve the security experience. Our cultures are well-aligned in terms of our business models as we both focus on delivering reliable security solutions through physical security expertise and a tech-forward approach.”
 
“This acquisition greatly accelerates the growth of our organization and enhances our off-duty law enforcement service offering while also positioning us as the fourth largest security services provider nationally,” said Mark Hjelle, CEO at Protos. “The combination of the companies will allow us to better serve clients across the nation with a large network of off-duty officers and is a great investment. We couldn’t be prouder to have Summit in our portfolio.”
 
Southfield Partner, Brandon Pinderhughes, commented on the transaction, “We are delighted to welcome the Summit team to the Protos family. The addition of Summit provides greater scale in the attractive off-duty segment and significantly enhances the range of services available to our valued customers.”
 
By continuing to invest in its management team, technology and service capabilities, Protos continues to further its mission to provide differentiated, leading total-value security solutions that deliver world-class service to its customers.
 

About Protos Security
Protos Security is a premier software-enabled security services provider offering guarding services, off-duty services and remote services for a diverse customer base across North America. Through a unique managed services model, clients gain access to a vast and agile provider network for security service delivery. Protos’ unwavering commitment to innovation and software excellence paired with real-time security program data insights ensures that Protos is a relentless advocate for clients and their people.
 
For more information, please visit www.protossecurity.com.
 
About Southfield Capital
Southfield Capital is a private equity firm that invests in high-growth, lower middle market companies in the outsourced business services sector. The firm targets companies with $4 - 15 million in EBITDA and partners with management to scale the business through a combination of organic and acquisition growth strategies.

For more information, please visit www.southfieldcapital.com.

Recent Posts


southfield capital acquires Contextual.ai to provide value creation
January 26, 2026
AI-driven Full-Service Business Contextual.io Complements Southfield Capital's Mission to Enhance Value Creation for Founders and Manager-Owners
Snow-capped mountain peaks under a pink and blue sunset sky, with dark rocky terrain in the foreground.
January 7, 2026
GREENWICH, CT – Southfield Capital, a premier lower middle market private equity firm, announced today that Kelvin Group, (“Kelvin”), a leading national provider of industrial and commercial mission-critical mechanical refrigeration services, process safety management and environmental compliance, has completed the acquisition of PermaCold Engineering, Inc. (“PermaCold”), a premier industrial refrigeration company headquartered in the Pacific Northwest. The acquisition of PermaCold represents Kelvin’s fourteenth acquisition since partnering with Southfield. Founded more than 30 years ago by industry pioneers, Steve Jackson and Randy Cieloha, PermaCold has built a reputation for excellence, innovation and reliability in the industrial refrigeration industry. The company is widely recognized for its expertise in ammonia and CO2 refrigeration systems as well as its ability to deliver complex, high-performance solutions to clients across the western United States. The integration of PermaCold into Kelvin Group's family of companies, which features reputable brands such as ARC Mechanical, Refrigeration Design & Service (RD&S), RC&E, HCG Associates, and JS Compliance, further solidifies Kelvin's standing as a national provider of mission-critical mechanical services. “Kelvin’s acquisition of PermaCold represents an exciting milestone as the company continues its national expansion strategy by entering the Pacific Northwest. PermaCold’s deep technical expertise, admired technician team and customer service focus makes them a natural partner for Kelvin,” said Harry Gray, CEO of Kelvin Group. “Together, we look forward to offering an enhanced set of capabilities to support our combined customer base.” “When we decided to sell, Randy and I were adamant in locating an organization that shares our company’s culture and values relating to customers and employees, and Kelvin more than achieved this goal,” said Steve Jackson, “We’re excited to leverage Kelvin’s national footprint to better serve our customers while staying true to the values that have guided us for more than 30 years.” Southfield Partner, Chris Grambling, commented on the transaction, "We are delighted to welcome the PermaCold team to the Kelvin family. PermaCold has built a phenomenal reputation in the Pacific Northwest and their addition bolsters Kelvin’s geographic coverage, establishing Kelvin as a coast-to-coast mechanical services provider." Deerpath Capital Management and Crescent Capital provided debt financing. G2 Capital Advisors served as the buy-side advisor to Kelvin. Finn, Dixon & Herling provided legal counsel to Kelvin and Southfield Capital. About Kelvin Group Kelvin Group is a national leader in the field of industrial and commercial mission-critical mechanical services, process safety management and environmental compliance. Its turnkey solutions provide design/installation, service and planned maintenance and testing and compliance of world-class mechanical systems for leaders in the food and beverage, cold storage, pharmaceutical, educational, health care, and process industries. Once engaged with customers, Kelvin assists business owners achieve mandated health, safety, environmental and regulatory compliance standards. For more information, please visit www.kelvin.cool . About Southfield Capital Southfield Capital is a private equity firm that invests in high-growth, lower middle market companies in the business services sector. The firm targets companies with $4 - 20 million in EBITDA and partners with management to scale the business through a combination of organic and acquisition growth strategies. For more information, please visit www.southfieldcapital.com .
Snow-capped mountain range under a pink and purple sunset sky; lower slopes are dark and forested.
September 4, 2025
Milrose Consultants and Southfield Capital Announce the Strategic Acquisition of Borne Consulting
Snow-capped mountain peaks under a pink and blue sunset sky, with dark rocky terrain in the foreground.
August 20, 2025
GREENWICH, CT – Southfield Capital, a premier lower middle market private equity firm, announced today that Security Services Holdings LLC, (“Protos”), a leading national tech-enabled managed services security provider in North America, has completed the divestiture of Mulligan Security (including MG Security Services) to Allied Universal. The transaction closed on July 3, 2025. The divestiture is a key step in Protos’ strategic plan to increase its investment in, and purposefully focus its efforts on, its managed services platform while accelerating growth. Protos’ singular focus is to drive a differentiated, data driven and tailored service experience for customers seeking a better way to manage their security programs. This divestiture reinforces Protos’ commitment to investing in high-growth areas where technology and operational excellence drive measurable client outcomes. Protos is a leading tech-enabled managed services provider in the security industry, with the largest North American supplier network of guarding and off-duty service providers, complemented by specialized security and remote video solutions. This divestiture underscores Protos’ disciplined approach to provide a differentiated client experience while accelerating its investment in a scalable, high-growth platform driven by technology and data intelligence. “With the divestiture of Mulligan, Protos will be laser-focused on driving a superior customer experience across its national footprint through our supplier managed model,” said Mark Hjelle, Protos CEO. “The Protos managed services model is unique to the marketplace and provides customers with improved operational transparency, flexibility and cost control.” Southfield Partner, Brandon Pinderhughes, commented on the transaction, “This transaction marks an important step in Protos’ strategic journey. By concentrating on its tech-enabled model, Protos is positioned to drive innovation, expand its capabilities, and deliver exceptional results for clients, regardless of their end market or their footprint inside North America.” About Protos Security Protos Security is a leading tech-enabled managed security services provider offering physical guarding, off-duty officers, specialized and remote monitoring services for a diverse customer base across North America. Through a unique managed services model, clients gain access to a vast and agile provider network for security service delivery. Protos’ unwavering commitment to innovation paired with real-time security program data insights ensures that Protos is a relentless advocate for clients and their people. For more information, please visit www.protossecurity.com. About Southfield Capital Southfield Capital is a private equity firm that invests in high-growth, lower middle market companies in the business services sector. The firm targets companies with $4 - 20 million in EBITDA and partners with management to scale the business through a combination of organic and acquisition growth strategies. For more information, please visit www.southfieldcapital.com.