I do not know of any standard for placement of serial numbers or logos on casino dice. The most common place for the serial number is the 6 side but I also have dice in my collection with the serial number on the 2, and 4 sides. logos are most often on the 1, and 2 sides as there is more room there for it. However a logo can be on any side of the dice where it will fit. I have some dice with 3 logos on them (1, 2, 4 sides).