Hi. I am presently working in the USA using an L1B visa sponsor by company A, but this company B in the USA also interested in me and they willing to sponsor me an H1B visa. Can I immediately transfer to them? I work for company A in 2 weeks time only. Is there any legal matters that company A, might ban me to work in the US? Do I still need to go back to my homeland for the stamped of H1B? Thank you.