Hi,
I got my H1B Receipt No dated back 2009 but my visa has not been initiated can i transfer it to new employer just with receipt number and not I797.
You may get cap-exempted petition filed using just the receipt number. The new employer prefers to have 797 approval notice to be sure that number belongs to you and was really approved. If you don’t have that, then employer has to rely on your word for it.