Differentiated from the US by a different SKU and from the Japan Reserve mug by size. The etched white logo appears to be the same for each of the set.
The European series includes an 8 Oz. Short mug apparently not found in the US or Japan. These were purchased at the Bank store in Amsterdam.
Additionally, the US Demi has a D on the bottom of the mug as it was used in store but the European version has a traditional bottom.
As of February 2015 these mugs can also be found at the Conduit Street store in Mayfair in London. (the UK flagship store)
Added by Badger