I've personally met one of the founders, and it was a damn shame how difficult it was for him to get a Visa to continue growing the company in the US.
We always hear this crap from politicians about how we have to help the "job creators" in the US. Well, Udemy's founders are a shining example of job creators that could use congress's help. Maybe they'll get the memo and finally do something about allowing the world's brightest to start and grow companies here in the US...