The puzzle is a Samurai Half Dominoes, where the rows and columns are counted as a whole. So if it's on the same height but different 9x9 grids, they still cant repeat. It's an interesting variation and funnily enough it doesn't even mean you need a lot more clues than normal. Just as a note, the Half Dominoes are a seperate image as that was easier.
12 Half Dominoes:
|Click to enlarge|