H1b validity

Hi ,

I have a friend you worked in US for 3 yrs on h1b and then left to work in a different country . Now he wants to come back to US will he have to go through the whole process of appling the h1b (lottery ) or will he be able to comtinue on the previous h1b visa ( provided an employer is ready to deal with whole h1b process )

He may be eligible for cap-exempt petition as he has a previously approved H-1 petition.