I don't think the country of residence is of any great relevance in copyright infringement (or perceived infringement) cases. Jimmy Page and Robert Plant are resident in the UK but that didn't stop Randy California from pursuing a case against them for allegedly nicking one of the Spirit riffs for "Stairway to Heaven".

That said, maybe there is a difference in US law and British law and it would be interesting to know whether such applies in this particular case.

Jack's probably got it right ...