H1B Transfer after 6 Years completion

[RG5001]

My 6 year terms on H1B will expire in Mar2015. I have received another 3 years extension (till Mar2018) recently based on the approved I-140 from my current employer company A.
- Now can I change the job to company B, based on this extended H1B beyond 6 years, that I received because of Permanent residency filed by current employer?

[raghvi]

My 6 year terms on H1B will expire in Mar2015. I have received another 3 years extension (till Mar2018) recently based on the approved I-140 from my current employer company A.
- Now can I change the job to company B, based on this extended H1B beyond 6 years, that I received because of Permanent residency filed by current employer?

Is A going to keep I140 active after you resign?