hi, I had an approved H1B visa from company A (which is ending on mid september 2011). I left company A and transfered my H1B to company B, which is currently pending (even after 5 months). Now, I intend to leave company B and work for a new company C (so far I dont have any offer).

my question is, can I transfer my H1B to company C even though my petition with company B is pending? If not what are my options?...please remember, I don't know if company A has notified USCIS about my employement termination. Also, what's the difference between notifying USCIS that I don't work for company A as opposed to H1B revoking/cancellation?