Sega Enterprises Ltd and Japanese computer services giant CSK Corp is to form a joint venture in the US by the end of November to research and develop interactive software for use in multimedia personal computers and video games. The new Sega Soft Inc company will be based in Redwood City, California, but other smaller investors will be brought on board, although they have not been identified as yet. The new company will start operations next month. CSK has a 20% stake in games machine king Sega.