TradeMark Security System

The TradeMark Security System (TMSS) was developed in order to prevent piracy, as it only allows games with the word "SEGA" in a certain part of the game's code to boot up. This did not prevent unlicensed games from being released on the Genesis/Mega Drive, however, and the lockout prompted a major court case that ultimately decided use of Sega's trademark to bypass the lockout did not violate US trademark law. Additionally, several older licensed games will also fail to boot on models supporting TMSS, while certain games (mainly those developed with Psy-Q development kit) proved the word testing was not exactly a whole word search.

Unused Logo#

This logo, including its palette entry, is loaded into the pattern table but is never shown at any point during the screen for some reason. It would have likely been used for the "SEGA" part of the disclaimer.

Revisional Differences#

Original Model#

The Genesis/Mega Drive models prior to the Model 1 VA6 lacked the TMSS. It was added in the next variation of the console.¹

Sega TeraDrive#

The Japan-exclusive TeraDrive, which is a 286 PC and a Mega Drive in a single unit, has a unique version of the TMSS ROM as part of its Mega Drive hardware. This version displays a very distinct screen.

Genesis/Mega Drive	TeraDrive

References#