How to understand the immigration status "above XXX"?

Question

Career in IT

The description of the proposed vacancy contains:
Immigration Status: Above H1B (GC/USC/H1B)
Who can explain, does this mean at least H1B (that is, a work visa), or everything but it?
As far as I know, the H1B visa is given for a specific employer and cannot be changed (or with great difficulty). What is the benefit of a new employer from my existing H1B visa?
I would also like to get more information on immigration status from more experienced immigrants: what other tricky wordings are found in vacancies (except for the standard US citizen, Green Card, visa-required), and how to understand them?

Answer 1

Above H1B means you can legally be in the country and work: i.e. citizenship, residence status (green card) or H1B (there are other visas that allow you to live and work, but the main ones are just listed on your line).
Transfer H1B is done according to a simplified scheme. You are already in the country, you do not have to wait long, the transfer is done outside the quotas at any time of the year. Although hiring a person with H1B is more difficult, it is still easier than doing everything from scratch (with a non-zero chance that the future employee will simply lose the lottery).

Answer 2

So you have the answer in brackets, these visas are higher than x1b