The term “AC21” is short for American Competitiveness in the 21st Century Act. Sec. 106 permits an employment-based Adjustment of Status applicant, whose Form I-485 Adjustment of Status application has been pending for more than 180 days, and whose Form I-140 Alien Worker Petition has been approved to change jobs, or employers, anywhere in U.S. to a same or similar job classification as described in the approved Form I-140 Alien Worker Petition.