While going through a large batch of hotel room key cards to see what scans were needed on the ChipGuide I came across a repeating theme. On many of the room key cards that have the ILKO / KABA logo on the reverse, many of the same design card actually have two different logos on the reverse. On some there is a small figure at the left of the ILKO logo while on others that figure is not there. Otherwise the cards are usually identical except for that small difference in the logo. I've been adding the new found cards as I come across them.

Here's one excample from the Gold Coast Casino in Calif. In this case there some extra text on the back too.