"Ain't Misbehavin'" is a 1929 stride jazz/early swing song. Andy Razaf wrote the lyrics to a score by Thomas "Fats" Waller and Harry Brooks for the Broadway musical comedy play Connie's Hot Chocolates. It was published by Mills Music. From Wikipedia
Classic characters and influential works from 1929, including novels by Faulkner and Hemingway, will soon be freely available for reuse.