I don't have a magnifier good enough to see for sure but it feels like all my blu-ray discs have a chamfered outer edge. I've always been able to tell the diffe

I don't have a magnifier good enough to see for sure but it feels like all my blu-ray discs have a chamfered outer edge. I've always been able to tell the difference from a DVD by touch. I don't know if the Wii U made the smoothing more significant and it doesn't seem that any discs I have changed the inner edge. As long as the overall dimensions are the same as a typical disc I can't see this being a form of DRM. Maybe a subtle way to mark discs as authentic. Nintendo pioneered the "golden seal" after all. I can also see how there might be a mechanical advantage. A rounded edge may have fewer problems while being inserted into the drive.