Labor & I-140 Approved. I-485 pending since June 2007. Recently renewed EAD & AP. I work for Company A and my wife works for Company B. Company B is a sister company of Company A. I filed for GC with Company A. Both my wife & I have recently renewed our EAD and AP. Company C took over (merger/ sold) companies A and B. Company C wants to change the employer name for both of us to Company C. And in doing so, Company C wants to us to use EAD instead of filing for new H1B. 1. Should we file AC21 for me and my wife? 2. If so can we personally file for AC21 or should the lawyer file for it? 3. Is there any particular format for AC21? 4. What documents are to be accompanied with AC21 filing? 5. To which USCIS center should I file the AC21 (My I-485 is at Nebraska, but recently renewed EAD & AP through Texas)? Company C's HR manager says that filing AC21 is not Mandatory. AC21 is just a provision to change the employer with 485 pending more than 180 days. Also, HR manager says they spoke to some lawyers and lawyers recommended not to proactively file AC21 cos in some cases proactively filing AC21 caused to rise a query from USCIS. 5. Is it mandatory to file AC21 while changing employer with EAD (with 485 pending for more than 180 days)? 6. What are the consequences for not proactively filing AC21? 7. Are there any negative impacts for proactively filing AC21? 8. In future if I change to another employer D, should I again file for AC21 and keep doing this process until I get my GC? Please advise. Sorry for the many questions.