Near perfect in every way. Only the most subtle bindery or printing defects are allowed. Cover is flat with no surface wear. Cover inks are bright with high reflectivity and minimal fading. Corners are cut square and sharp.
Staples are generally centered and clean with no rust.
Cover is generally centered and firmly secured to interior pages. Paper is supple and fresh. Spine is tight and flat. Yes, comics in this grade do exist, but they are extremely rare for one simple reason - this is the most subjective of all the grades. What qualifies as Mint to one person may have a small, almost unnoticeable flaw that downgrades it to Near Mint for someone else.