H1B visa change to new employer

Currently I am on L1B visa with employer A. Employer B has sponsered H1B visa for me in April 2012 and H1B visa is approved in May 2012 with COS effective from Oct 1st 2012.I left US in May 2012.

I came back to US in October 2012 on L1B visa.Currently I am on L1B visa.

Do I need to submit to Immegration regarding h1B visa since I am still on L1B visa even after october ?

Can I transfer my H1B visa to employer C with out working for Employer B (who has sponsered my H1B visa) for a single day? or Is there a minimum duration I have to work for Emploer B?

Please help.

As you entered US after Oct 1, you are currently on L-1 visa status. So the employer needs to file COS from L-1 to H-1 in order to start working on H-1.

It is also possible for C to file H-1 transfer along w/ COS for you. Once approved, you can start working for C. There is no requirement to work for B prior to this as you are currently on L-1 and not H-1.

Thank you Saurabh.

In my H1B petition it is mentioned as " the above petition and change of status is approved."

Is that mean COS is also approved along with petition?
Even in that case, can I transfer my H1B to employer C?

Please clarify.

It was approved to start from Oct 1. Had you entered US prior to Oct 1, you would have automatically made use of this approved COS and would have been on H-1 visa status from Oct 1.

However, you entered US after Oct 1, and so the approved COS didn’t apply to you. You are now on L-1 visa status, and COS needs to be filed from L-1 to H-1 in order to start working on H-1.