[kenneth]

3 years term per approval. But you have to apply again every time you change jobs. I started with one company, then was founder of a startup, re-applied there, and moved it to another company.

Re-applying is easier once you've been approved once.

[ameen]

What's the reapplication process like? Do you need to have done something exceptional from the time of the previous one's expiry to warrant an extension?

[SeoxyS]

I've never done an extension, just a transfer. It was pretty routine; you just file the application again just like the first time. Not much of a difference; other than the previous approval making your chances of getting approved once more significantly higher.

The first time, I had to get a new visa stamp (which required going back to my home country to get it from the U.S. embassy); the second time I kept the same visa stamp and a little piece of paper in my passport showing the transfer. It's mostly useful as a reference of the case number when I get asked about my employer (which is different than the one shown on the visa stamp) when I travel back to the US from a trip abroad.

[n00b101]

I see. How does EB-1 relate to this?

[SeoxyS]

EB-1 is basically a green card version of the O-1 (i.e. an immigrant visa, not tied to your ongoing employment). Once you have an EB-1 you can freely change jobs, start companies, do consulting part time, etc. The requirements are essentially the same as the O-1, but evaluated much more strictly.