What are those little permanent marker dots on the bottom of my soda cans?

Question

There is often these dots, usually about 3, that look like permanent marker dots on the bottom of the soda cans. I was just wondering if they have any meaning? Maybe a number of times it was recycled or something?

Answer 1

From the way that you described them, they sound like little permanent marker dots.

however most of the aluminum cans that we are getting not have been melted down and remade in to cans again many times.

Answer 2

They are probably the color register dots. When multiple colors are being applied they need to keep each color separate.