In a recent decision, Star Direct, Inc. v. Del Pra www.wisbar.org/res/sup/2007ap000617.htm the Wisconsin Supreme Court determined that where an employment contract contains restrictive covenants which address separate specific interests of employers, the fact that one of those covenants is overbroad and therefore illegal does not necessarily render other covenants unenforceable.
The contract in that case contained provisions restricting the employee from engaging in business similar to that of the employer, restricting him from contacting past and present customers of the employer, and requiring the employee to hold certain information derived from the employer confidential. The court determined that the covenant restricting the employee from engaging in similar business was overbroad, but that the other covenants addressed separate legitimate concerns of the employer which would remain enforceable. Therefore, those covenants are divisible from the invalid covenant.