Yes, it can be extended any number of times. But each and every O-1 approval is also highly subjective and discretionary. The standard is somewhat lower than E

Yes, it can be extended any number of times. But each and every O-1 approval is also highly subjective and discretionary. The standard is somewhat lower than EB-1. While EB-1 requires what Congress calls "extraordinary ability", the O-1 requires "exceptional ability". Again, the way things work is that whichever officer looks at the case, subjectively decides if it qualifies (in his/her opinion). Nothing like the highly-objective points-based skilled immigration system you have in some countries.