Can visa stamp from one employer be used for other employer?

I am working for Employer A in US. My Visa stamp expires on September 2014.

I have got a job offer from Employer B and they have filed my h1 transfer . They want me to join as soon as they get the receipt from USCIS.

  1. Should I join them as soon as they get the receipt? What happens if the visa gets denied later on ?

  2. The Visa stamp shows the name of the employer A. Can I use the same stamp to work for Employer B or I need to go for stamping again?

  1. Should I join them as soon as they get the receipt? What happens if the visa gets denied later on ?

You can…if you are sure that your transfer will get approved. If denied your old petition is still valid but I am not sure if your employer would take you back. so you would be jobless

  1. The Visa stamp shows the name of the employer A. Can I use the same stamp to work for Employer B or I need to go for stamping again

Can use the stamp for A till the visa is valid