H4 EAD & Switching employer


I am currently working for a company A and have I140 approved over a year ago and got a EAD card to my dependent, it is valid until 2023. I am planning to switch to a new employer and they would start the perm process again. Would this affect the validity of existing EAD card?

No, as far as primary H1B and H4 are in valid status, H4 EAD may be used by the beneficiary till its expiry.
When you transfer your H1B to new employer, make sure you also file for H4 EOS. No need to file EAD extension.