H1-B transfer to another company...

[rxraza]

hi all:

I work for company 'A' on H1-B , I have got an offer from company 'B'. Do I need permission from company 'A' to transfer my H1 to company B

Also, Can I work partime if Company 'A' wants me to stick with them until they get a replacement and at the same time I work for company 'B' on H1. In other words can I work for both companies on Individual H1's?

Thanks in advance.