WAicom
WAlchemist (company)
WAlphaDream
WAmbrella
WAmusement Vision
WAQ Interactive
WAspect Co.
WCareer Soft
WCavia (company)
WCing
WContrail (company)
WData East
WDimple Entertainment
WEIM (video game developer)
WELF Corporation
WEnix
WEntertainment Software Publishing
WFill-in-Cafe
WGamepot
WHacker International
WHudson Soft
WHuman Entertainment
WImageepoch
WInterchannel
WKID
WKoei
WMarigul Management
WMarvelous Entertainment
WMileStone Inc.
WMitchell Corporation
WNamco
WNintendo Integrated Research & Development
WNintendo Research & Engineering
WNintendo Research & Development 1
WNintendo Research & Development 2
WNintendo Software Planning & Development
WParam (company)
WPsikyo
WQuest Corporation
WQuintet (company)
WRiverhillsoft
WSega AM1
WSega AM3
WSETA Corporation
WSmilebit
WSpike (company)
WSuzak Inc.
WTechnōs Japan
WThinking Rabbit
WToaplan
WTokyo Shoseki
WUEP Systems
WUkiyotei