Sonic Jam
"Sonic Jam" is a compilation which contains the four main "Sonic the Hedgehog" games released on the Sega Genesis: "Sonic the Hedgehog", "Sonic the Hedgehog 2", "Sonic the Hedgehog 3", and "Sonic & Knuckles". Unlike future "Sonic" collections, "Sonic Jam" does not use a Genesis emulator; the games are proper ports, and all are nearly identical to the original Sega Genesis releases, with the exception of minor bug fixes. "Sonic Jam" emulates "Sonic & Knuckles" "lock-on technology"—a special feature that allows the player to merge elements of "Sonic & Knuckles" into previous games, resulting in changes to the level design as well as the choice to play as Knuckles the Echidna in "Sonic the Hedgehog 2" and Tails in "Sonic & Knuckles".
Sega v. Accolade
As a result of the piracy and unlicensed development issues, Sega incorporated a technical protection mechanism into a new edition of the Genesis released in 1990, referred to as the Genesis III. This new variation of the Genesis included code known as the Trademark Security System (TMSS), which, when a game cartridge was inserted into the console, would check for the presence of the string "SEGA" at a particular point in the memory contained in the cartridge. If and only if the string was present, the console would run the game, and would briefly display the message: "PRODUCED BY OR UNDER LICENSE FROM SEGA ENTERPRISES LTD." This system had a twofold effect: it added extra protection against unlicensed developers and software piracy, and it forced the Sega trademark to display when the game was powered up, making a lawsuit for trademark infringement possible if unlicensed software were to be developed. Accolade learned of this development at the Winter Consumer Electronics Show in January 1991, at which Sega showed the new Genesis III and demonstrated it screening and rejecting an "Ishido" game cartridge. With more games planned for the following year, Accolade successfully identified the TMSS file. They later added this file to the games "HardBall!", "Star Control", "Mike Ditka Power Football", and "Turrican".