As 2026 comes to an end, the co-founder and longtime Chief Operating Officer at digital advertising technology and services company AdCellerant will step away from day-to-day duties while remaining on the Board of Directors. That sees the appointment of a “veteran product and technology” executive to serve as COO starting on January 1.
Taking the post in 2027 is Allen Klosowski, who previously served as Sr. VP at Epsilon. He’ll succeed Shelby Carlson, who will continue guiding the company’s long-term strategy and governance as a board member.
“Helping build AdCellerant has been the greatest privilege of my career,” said Carlson. “As we’ve grown, we’ve always believed in surrounding ourselves with exceptional leaders who can help take the company to new heights. Allen brings an extraordinary combination of operational excellence, product leadership, and deep industry expertise. I have tremendous confidence in his ability to help lead AdCellerant through its next chapter. I’m incredibly proud of what we’ve built together over the past thirteen years, and I believe our strongest years are still ahead of us. I’m excited to continue supporting the company’s long-term strategy from the Board.”
Commenting on Klosowski’s arrival, AdCellerant co-founder and CEO Brock Berry said, “Over the last thirteen years, we’ve built AdCellerant into one of the industry’s leading technology-enabled advertising platforms by making sophisticated digital marketing accessible to organizations that historically lacked enterprise-level solutions. Allen is exactly the leader we want as we invest in the talent, technology and innovation that will define the next generation of advertising. His experience at Amazon, Epsilon, and SpotX, combined with his operational leadership and strategic vision, positions us to accelerate our product roadmap, strengthen execution across the company, and continue delivering exceptional value to our partners.”
Prior to Epsilon, Klosowski held leadership roles at Amazon, where he helped develop the company’s customer-facing media planning tools for Streaming TV, accelerating the shift of advertiser spend from Linear TV to Amazon’s DSP. He also developed products supporting Amazon’s omnichannel advertising, programmatic media, identity, and measurement solutions.
“AdCellerant has built one of the industry’s most compelling platforms for helping media companies, agencies, and brands simplify the complexity of digital advertising while delivering better outcomes,” Klosowski said. “That customer focus, the pace of innovation behind it, and the outstanding company culture are why I’m excited to join the team. I’m ready to use my experience innovating at scale across SSPs, DSPs, agencies, and publishers to accelerate the next generation of solutions AdCellerant is building for its customers.”
