Lawsuits
Esber had earlier threatened a group of dBASE users who were attempting to define a standard dBASE file format. With this standard, anyone could create a dBASE compatible system, something Esber simply wouldn't allow. But as soon as they were issued the cease-and-desist, they simply changed their effort to create a "new" standard known as "xBase".
Esber had previously decided to sue one of the clone companies involved, then known as Fox Software. By the time the case worked its way to court in 1990, Fox Software had released FoxPro and was busy increasing market share. If the court case was successful, Ashton-Tate could stop FoxPro and use the precedent to stop the other clones as well, allowing dBASE to regain a footing and recover from the dBASE IV incident.
These hopes came to an end when the case was thrown out of court. During the initial proceedings it was learned that dBASE's file format and language had been based on a mainframe product used at JPL, where Ratliff had been working when he first created Vulcan. The credibility of Ratliff was jeopardized by his alternate claims of ownership while at Ashton Tate and then supporting the roots at JPL after he left. All the facts were never sorted out and Ashton-Tate's competitors had a self-interest motivated field day in writing amicus briefs.
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. Unfortunately, his earlier ruling had already done considerable damage. Eventually, as part of the merger with Borland, the U.S. Justice Department required Borland to not assert copyright claims in menu commands and the command language of dBASE.
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