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Stout Advises CSSI on Sale to Proteus

September 26, 2023

Stout announced today that its client, CSSI, Inc., has been acquired by Proteus Capital Solutions. Stout served as exclusive financial advisor to CSSI in connection with this transaction.

Founded in 1990 and headquartered in Washington, DC, CSSI is an industry leader working to improve national air transportation networks. CSSI’s collaborative work with its government customers has improved the safety of the nation’s critical air transportation infrastructure, increased the efficiency of the National Airspace System (NAS), and facilitated the modernization of both NAS and Department of Defense systems and capabilities. CSSI has over 175 employees and operates in five locations while serving customers across the United States and around the world.

Proteus Capital Solutions is a Maryland-based private equity firm focused on lower middle-market control investment opportunities in the aerospace, defense, and government services (ADG) markets. The vision of the firm is to build the next generation of middle-tier ADG competitors. The firm’s professionals have spent the vast majority of their careers in the ADG sector and provide deep networks, operational and investment expertise, knowledge of government customers, and strategic insights to the firm’s portfolio companies.

“I am proud of our employees and what our team has built over the years, and we are excited to expand our success as we partner with Proteus,” said Kelly Caccetta, who has assumed the role of CEO in addition to her position as CSSI's President. “We felt an immediate synergy, and we look forward to leveraging Proteus’ knowledge and expertise as an experienced government services and technology investor. As I step into the role of CEO, I plan to build on our core capabilities while expanding our customer base and continuing to deliver best-in-class solutions.”

“After 30 years of building a business, this process brought a myriad of emotions,” said Cynthia Castillo, who retired as CSSI’s Chairman and CEO after a distinguished 30-year tenure. “Not only did Stout provide great perspective, they also provided invaluable knowledge, support, and attention to detail throughout the transaction process. I would highly recommend the Stout team for any future transaction needs.”

“I have known and watched Cynthia’s unparalleled commitment to her company, her employees, her clients, and her industry for nearly twenty years,” said Stout Managing Director Cameron Hamilton, who led the execution of the transaction. “It has been a pleasure to help her and her management team find a successful partner to continue their growth going forward.”

Stout’s Alexander Wilson and Eric Fahmi assisted in executing the transaction.

Womble Bond Dickinson provided legal services to CSSI. Holland & Knight served as legal advisor to Proteus.

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