Complex sentence: He was the class commencement speaker at his graduation, after which he joined the Dayton-based E.F. McDonald Company (then Cappel and McDonald) developing worker incentive programs for the food and pharmaceutical industries.
Split into simpler sentences: He was the class commencement speaker at his graduation. Upon graduation he joined the Dayton-based E.F. McDonald Corporation (then Cappel and McDonald) developing worker incentive programs for the food and pharmaceutical industries.