H1B revocation process and different status in case history

[myh1b112233]

What triggers H1B revocation when employee transfers from Company A to B? 
Approved with Company A in 2014, joined Company A, transfers to Company B and continues. 
When he looked online case status, his case story showing like this. 
What triggers his H1B and why they NOIR and then sent revocation notices? 
Will this revocation has any effect on subsequent transfers considering current trends and Immigration policies? 

Following are time lines of Company A H1B or I-129 history. 
xx/xx/2017 
We revoked the approval of your case and mailed you a revocation notice. 
xx/xx/2016 
We mailed you a notice indicating our intent to revoke the previous approval decision made on your case. 
xx/xx/2014 
We approved your Form I-129, Petition for a Nonimmigrant Worker

Less 

[gouthamsworld]

Two things can trigger revocation

1. Request from petitioner

2. USCIS randomly auditing previously approved cases

[JoeF]

3 hours ago, gouthamsworld said:

Two things can trigger revocation

1. Request from petitioner

2. USCIS randomly auditing previously approved cases

And #1 is mandatory if the person leaves the employer. The employer is required by law to inform USCIS if the person on H1 no longer works there.

[NotAnAttorney]

He needs to get with his old employer if possible and find out on what grounds NOIR was issued.

If it's Misrepresentation or fraud, then he would have future impact. As this is his first H1B from cap quota, and if this is revoked for fraud/misrepresentation then he will not be cap exempt anymore, which means can't get extensions or transferred.