I am in 6th year of stay in US. I have spent 5 years in the beginning on L1B visa. Recently I have been moved to H1B visa approved for 3 yrs. I have I140 approved. That's the reason I got the 3 yrs extension. Now I have got a good offer. Can I change the employer without worrying about visa issues since my GC process will be halted for a while while I change employer?
No one can guarantee you will not have issues. Issues are possible even in the cleanest of cases.
Your employer needs to retain an experienced immigration lawyer to review all the facts, advise them, and handle the case. Your employer can find one through http://www.ailalawyer.com.
J Charles Ferrari Eng & Nishimura 213.622.2255 The statement above is general in nature and does not constitute legal advice, as not all the facts are known. You should retain an attorney to review all the facts specific to your case in order to receive advise specific to your case. The statement above does not create an attorney/client relationship. Answers on Avvo can only be general ones, as specific answers would require knowledge of all the facts. As such, they may or may not apply to the question.
It is highly recommended your employer contacts a business immigration attorney who will advise them properly.