Courtesy of Diamond, we’ve been posting their top sales charts for 2011 today (more are coming) — but one question keeps coming up. Diamond releases charts for both “Indie” publishers and “Small” publishers. What is the difference? When you see Random House — the world’s biggest publisher — on Diamond’s “Small” chart, it seems paradoxical. Well, Diamond has provided us with some definitions.

“Independent” means a non-premier publisher, so anything outside Marvel, DC, Dark Horse, Image or IDW would be on these charts. These five publishers are all in the front of Diamond’s catalog and enjoy many other privileges.

“Small Press” is defined by Diamond as publishers outside the top-10 bestselling publishers over the previous six months. “By offering these breakdowns of the bestselling small press comics and graphic novels, a spotlight is shown on these publishers, affording them recognition for their strong sales in a crowded marketplace,” explained a Diamond spokesman.

If you noted the Top Ten publishers list we posted earlier, you’ll see that “Small” would include D&Q, Fantagraphics, Pantheon, Oni, Legendary…publishers who all had bestsellers in 2011. Comparing the top 500 to the top 250 chart is an interesting business.