The short answer is: The warranty must cover damage not caused by your modification. There are no countries i'm aware of that require you warranty damage cause

The short answer is: The warranty must cover damage not caused by your modification. There are no countries i'm aware of that require you warranty damage caused by user modification. Lots of countries require that you do not void the entire warranty, or refuse service, of any damage not caused by the modification, and generally the manufacturer has to show the damage was caused by the modification if they want to refuse service. In this case, Fuji is trying to void the entire warranty. That is not legal in a lot of countries.