Ron, I've been researching a lot on this topic lately and seems people and few attorneys are really confused with the thin line of difference with changing employers on approved i-140 before and after AOS. I have been going through your comments to other posts and few other posts from trackitt which made perfect sense. I am putting together a collated info Re this topic for your blessing. When working for Company A and I-140 gets approved and the employee wants to move to company B: - The employee can assume any role/designation/job description with company B (need not be same/similar) - The new employer will be able to use the existing I-140's PD to port the date and possibly to EB2 (if it was earlier in EB3 and the new job requires EB2 requirements) - Its good to provide the new employer with the copy of I-140 but the filing number will also help to port - New employer will need to file the PERM again before filing the new I-140 petition - Not mandatory to wait for 180 days with Company A after I-140 approval before moving on - All the above statements hold good before or after the initial 6 year H1B term When working for Company A and I-140 gets approved and I-485 (AOS) is also filed when the date was current. The employee wants to move to company B: - This is the typical AC 21 case and the employee needs to ensure the new job needs to be similar/same. USCIS determines this by job codes - The new employer will not be filing a new labor (PERM) which is why it is required that the new job be similar or same since the old PERM is being used - This move needs to take place only after I485 has been pending for 180 days when with company A - All the above statements hold good before or after the initial 6 year H1B term Please let me know if any statement is incorrect. You expert thoughts will be greatly appreciated. There has been a lot of confusion in these 2 cases which are the similar actions only taking place at different stages. Thank you.