SNK Patents
US Patent [[1]] filed in February 1996 by Yoshihiko Hasegawa and Takashi Yamatani describes the NeoGeo's video hardware, VRAM layout and methods for creating sprite effects with the scaling functions (used in World Heroes 2).
US Patent [[2]] filed in April 1995 by Yoshihiko Hasegawa describes the MVS BIOS functions, like game-specific parameters, play time stats and time keeping.