"A game playing system includes a use permission tag provided for use in a game disk for a user of a game, a disk drive, and a reproduction device for reproducing the game," reads a line from the patent's abstract. "The disk drive reads out a disk ID from the game disk. When the game is to be played, the reproduction device conveys the disk ID and a player ID to the use permission tag. The use permission tag stores the terms of use of the game and determines whether a combination of the disk ID and the player ID conveyed from the reproduction device fulfills the terms of use or not." 
 
In the patent filing, Sony said in a content business like the games industry, it is "vital" to redistribute a portion of the proceeds from sales to developers, who do not see a dime from secondhand sales. Sony said though the secondhand market may expose new gamers to a particular title, in the long run, this does not benefit developers. 
 
"In such a scheme where the electronic content is bought and sold in the second-hand markets or the like, the sales proceeds resulting therefrom are not redistributed to the developers," reads a line from the filing. "Also, since the users who have purchased the second-hand items are somehow no longer potential buyers of the content, the developers would lose their profits otherwise gained in the first place."