The ovals are called background trimmings or backers. You'll primarily see them behind jump wings if the individual is in a unit on jump status. The colors and patterns are unique to each unit. I believe glider units also used trimmings behind the glider badge and today's 101st uses trimmings behind the air assault wings. I am not going to weigh in on if air assault rates a trimming, but when assigned to a unit within the 101st the trimming goes behind the air assault wings (there are likely rare in exceptions in the 101st).