But the USCIS generally approves petitions to change from one employer to the next if the gap between jobs is short. 30 days is acceptable
It comes down to pay not skills. FB could afford the people in the US with those skills, they are just looking for employees that are cheaper, and they tend to be Indians and Chinese because they value being on US soil more than anyone else. I heard a phrase recently "India has a population of 1 Billion and 900 Million want to be in the US".
The competition is fierce and I don't blame them.
http://www.nytimes.com/2016/01/26/us/lawsuit-claims-disney-c...
Super shady, but it was a fleeting attempt at plausible deniability on behalf of Disney execs.
Sometimes, I'm quite the fan of China taking its executives out and executing them for breaking the law.
That said, if your employer sponsors you for a green card while you're on an H1B you are quite trapped in your job, and I wouldn't be surprised if people found their wages not rising as much as they would have otherwise.
The H-1B part comes in when the contractor hired H-1B holders to fill those slots.