Sosna has also worked as a chief of staff and assistant athletic director for the NCAA's Cincinnati Bearcats and USC Trojans and as an administrator for the NFL's Cleveland Browns and Detroit Lions.
[1] There, Sosna assisted in managing the salary cap, negotiating contracts, and developing free agent evaluations.
[2][3] Sosna followed Bohn to the USC Trojans in December 2019 and worked as their chief of staff and executive senior associate athletic director focusing on their football program,[1] where he was considered key in the hiring of head coach Lincoln Riley in 2021.
[4][5] Sosna was hired by the NFL's Detroit Lions in July 2022 as the senior director of football administration, serving as their primary contract negotiator.
[9] He participated in the 2010 March of the Living trip to the Auschwitz concentration camp and co-founded an nonprofit organization in high school known as Project 6 Million that raised awareness for victims of the Holocaust.