Legal Question in Intellectual Property in Pennsylvania

Re: Intellectual Propert

The first step would be to determine if your fiance signed a proprietary rights or similar agreement with the employer. Many of these agreements prevent the sort of outside development of similar programs as described in your post. Also, if the program would be considered a trade secret of the employer, your fiance may be violating it by creating and marketing a similar program.

The answer also depends on whether or not the "similar program" is derivative of the work created for the employer, in which case there may be a copyright infringement problem.

The bottom line is you should have a qualified attorney review the specifics of the situation in order to properly advise your fiance. This is a complex area of the law.