When a group of Tennessee doctors reached out to Gary Elden, the Chicago lawyer suggested they needed to find an attorney closer to home. But the doctors were entangled with a hospital system that was the largest employer in town—a potential defendant, they insisted, that no one wanted to sue.

Elden agreed to take their case, but the only way he could pursue the litigation affordably was to file it as a class action. Then, in 2015, his firm merged with Shook, Hardy & Bacon, which is almost always on the defense side of class actions.