You have it pretty much correct.USCIS evaluates whether the job offered is a specialty occupation as required for an H-1B, whether the required employer/employee relationship exists, etc. USCIS may also evaluate whether the beneficiary, if here in the US, has been maintaining valid immigration status up to the time of filing such that a change, amendment, or extension of status can be granted in the US.Both the DOS and CBP are essentially adjudicating admissibility (though as Iu2019ll discuss in a bit, the lines are a bit blurry - they may also inquire into ongoing H-1B eligibility).In the case of an H-1B approved by USCIS for someone abroad, only H-1B eligibility (job, degree, employer/employee relationship etc.) has been evaluated to see if there IS a reason under existing law to grant that status.But, itu2019s up to both the DOS at the consulate and then CBP to see if thereu2019s a reason NOT to allow the person in - criminal record, terror watch list, etc. USCIS wouldnu2019t have looked into this at all, and both DOS during the visa stamp application and CBP upon entry would look into this.DOS at the consulate, and perhaps CBP upon entry, may also again look into the substance of the H-1B . Perhaps USCIS approved an H-1B that was completely approvable on its face, but the DOSu2022 local consulate has specific knowledge that the degree certificates and transcripts presented were from a local school recently busted as a fraudulent u201cdiploma millu201d - so they may realize the person doesnu2019t have the required degree after all. CBP may determine upon entry that though an H-1B was valid when granted, the person no longer works in the job specified for the petitioning company and so is fraudulently using that H-1B to enter for some other purpose not permitted by the H-1B.