Pretty much what sam said- though there are some grey areas.
I did a repair job for free where the user had cracked the scales off while chopping down a tree with his knife- hit the scales on the trunk too many times. I was actually really excited, wanted to see what the knife looked like after a couple cords of wood!
So far I've been able to get by with person-to-person contact on this, and haven't stated a warranty explicitly. I imagine at some point I will have to.
I've had 5 repair jobs so far- the handle separation, two times where there was corrosion in shipment, which was light and easy to fix, one edge chipping that made no sense at all. I reprofiled slightly and chopped a brass rod without any chipping, and one of my VERY early knives is here getting reprofiled to match my better work.