How long is an unused or interrupted H-1B valid

[TechWorker1]

I am asking this about a friend as I could not find a definite answer anywhere.

My question has two scenarios:

1.

H-1B was approved by USCIS, but never stamped or worked in the US. How long of a time do this person has from the date of approval of the H-1B, before it becomes invalid and requires this person to go through the lottery and approval process again ?

2. 

Person started working in the US but at about 1-year mark, he/she had to go back home fir personal reasons. Hence the company did not keep the position but did not revoke the visa neither. How long of a time he/she has, to come back to the US with an H-1B transfer or re-hiring by the same employer, before needing another lottery and approval process ?

Thanks

[JoeF]

If a person neither worked on the H1 nor got the H1 visa stamp the person has not been counted for the quota, and a new employer would have to file an H1 in next year's quota.

If a person has worked on H1 and left the job the employer was required by law to inform USCIS of that fact that the person no longer works there. If the employer didn't do that the employment relationship hasn't ended and the employer has to continue paying the person. That has no effect on the person's ability to get a new H1 from another employer. The person can sue the old employer for back pay, though.

[gopalakrishnach]

1. If approved H1B was first H1B and from your post it looks like they never got it activated. It will get invalid on the date that is printed on the approval form. I am not sure whether your friend needs go through lottery again or not but your friend needs new petition and visa stamp to come to USA and work.

2. He/She can come back to USA as  per their schedule. Any employer can submit new petition anytime of the year to claim remaining time on H1B. No lottery just apply anytime .

[Zodiac System]

Question 1:

Is this person's job with the same employer still available?  Should be able to get a stamp and come to US  to this same employer (when stamping re-opens). 

Question 2: 

Is this person's employer still running the paycheck when he/she went back home for personal reasons?  Should be able to come back to the same employer.  

Lets see what other experts advise