[mingfli]

No, that only applies to green card applications through work. General work visas don't usually have this restriction.

[st3v3r]

H-1B explicitly does.

[mingfli]

Umm, no it doesn't. http://www.uscis.gov/eir/visa-guide/h-1b-specialty-occupatio...

[ConfuciusSay]

It doesn't, it's a misconception.

You see often enough companies hiring H1-B's, have their American equivalents train them, and then fire the American workers.