"CVA's proprietary, tamper-evident holographic sticker provides assurance that the comic book you own has met our strict standards for outstanding eye appeal and superior structure within the numerical grade assigned by CGC.
CVA's distinctive sticker allows collectors, dealers and investors, with any level of experience, to easily identify these premium-quality examples in any grade. A CVA endorsement adds value for anyone interested in the CGC graded comic book market, buyers and sellers alike."
I think Butters once came up with a similar criteria...