Both Ruby and Spears started out as sound editors at Hanna-Barbera, and later branched out into writing stories for such programs as Space Ghost and The Herculoids. In 1969, they were assigned the task of developing a mystery-based cartoon series for Saturday mornings, the result of which was Scooby-Doo, Where Are You!. They were also writers and producers for DePatie–Freleng Enterprises, particularly for The Barkleys and The Houndcats.
Ruby-Spears Productions was founded in 1977 while Ruby and Spears were network executives at ABC supervising the Saturday morning programing. ABC Entertainment president Fred Silverman wanted to create competition for Hanna-Barbera, which was providing a bulk of the Saturday morning content for all three major networks and concerns of quality began to arise. The company's credits include the animated series Fangface, Goldie Gold and Action Jack, The Plastic Man Comedy/Adventure Show, Thundarr the Barbarian, Rubik, the Amazing Cube, the 1983 version of the Alvin and the Chipmunks series, Mister T, Sectaurs, The Centurions, the 1988 Superman series, the Police Academy animated series and the American Mega Man cartoon series (rights now owned by DHX Media in library).
Only one series, Piggsburg Pigs!, used Canadian voice talent rather than American one like most of their other cartoon shows. Ruby-Spears was also responsible for the animated sequence in the 1988 film Child's Play.
The Ruby-Spears studio was founded in 1977 as a subsidiary of Filmways and was sold in late 1981 to Taft Broadcasting, becoming a sister company to Hanna-Barbera Productions. In 1991, Ruby-Spears was spun off into RS Holdings while most of the original Ruby-Spears library (its pre-1991 library) was sold along with Hanna-Barbera to Turner Broadcasting System, which in turn merged with Time Warner in 1996. The Ruby-Spears studio closed in 1996.