Complex sentence: In 1980, his father had bought out his partner, then gave the shares to Cline, who was then 21 years old and was taking a degree in psychology at Marshall University in Huntington, West Virginia.
Split into simpler sentences: In 1980, Cline's father bought out his partner then gave the shares to Cline, who was then 21 years old. At that time, he was studying psychology at Marshall University in Huntington, West Virginia.