When the federal judge reviewed the work of his clerks he overturned his earlier ruling, and decided to hear the case on whether or not Ashton-Tate owned the language. In April 1991, the judge vindicated Esber's decision to protect Ashton-Tate's investment of several hundred million in the development and marketing of dBase, by ruling that Ashton-Tate did own the language. Unfortunately, his earlier ruling had already done considerable damage. Eventually, as part of the merger with Borland, the US Justice Department required Borland to not assert copyright claims in menu commands and the command language of dBASE. This paved the way for Microsoft to buy Fox Software.