Your employer should only own your work outside of work hours only if you have a non-compete, is directly related to the work you perform, is derivative of code

Your employer should only own your work outside of work hours only if you have a non-compete, is directly related to the work you perform, is derivative of code that you access from work, or you indentured all of your code contractually. Anybody know if a GPL versus "we own everything you do" situation has arisen yet in the courts?