I think istock would make sure they pay people through their Canadian finance offices, to get around this. I can't understand why shutterstock don't move their finances outside the US. It seems every other big internet company has done that with no problems, so why can't SS? Google, Facebook, Yahoo!, e-bay,Amazon and many more are located in Ireland, I wonder why
I suspect the 12.5% corporation tax has a large part to play as do the tax treaties with US, EU and a lot of other countries.
But the English speaking highly qualified workforce plays no small part either.
As do labour laws, productivity levels, etc