However, when you completely change employers at any point in the green card process after the I-140 has been filed, you must have that employer file a completely new I-140. Additionally, that employer also needs to obtain a new PERM Labor Certification for you if your green card requires one. The reason for having to start from square one is this. Your PERM is based on a distinct position for a specific employer in a particular geographic location. If any of those things change, then the PERM can no longer do its job, which is to protect the jobs of U.S workers. Because of this if you are changing jobs before or after I-140 approval and your employer changes as well, a new PERM must be obtained, which means that another recruiting period must be run and your employer will be exposed to the possibility of an audit.