I am currently in USA and working for Company A. My wife and child are in India and they have a stamped H4 visa on their passport under the name of Company A expiring on Dec 2015. Now I got a job offer with Company B, who will be filing an H1-Transfer petition. I just wanted to know once my H1 Transfer is approved, if my wife and child will be able to travel to USA with the H4 visa stamp under company A and copies of approved I-797 under Company B, or do they need to again go for a H4 visa stamping in India under Company B.