from what i understand ip law pertaining to fashion is very weak. you can essentially rip off of other designers with little retribution (see urban outfitters, h&m, etc.) Doesn't exist in the US, really. Off the top of my head Japan and the EU have some protections. The CFDA is trying to push a bill through for like the 5th time in as many years called the Design Piracy Protection Act (DPPA). You can search the NY Times site for some concise articles. Most of the lawsuits you see in the US are trademark-based suits. Copyright-based suits fail because copyright doesn't exist. There's a long, drawn out explanation for this but that's just not going down.