There are strict limits on what a third party (you) can obtain with a civil subpoena. First, you must give advance notice to the employee of your intent to subpoena the records so the employee has an opportunity to object to your subpoena on privacy or other grounds. Further, the records sought must be relevant to the issues in the proceeding in which the subpoena is issued. You are not allowed to go on a fishing expedition merely because you wish to obtain your ex's employment information. If you are in a divorce proceeding, you are entitled to obtain the opposing party's tax returns and other income information relevant to issues of spousal and child support, but not a wholesale reproduction of his or her entire personnel file. I strongly suggest you consult with a lawyer on this issue.