I was just reminded from reading the 'what is your latest matrix quad LP' thread that Arista records did quad LP's, and as far as I know Arista was a subsidiary of RCA and they're all now owned by Sony.
Arista didn't do very many quads, but one of them is one of my favourite jazz/funk albums, 'Back To Back' by The Brecker Brothers. It's an absolute powerhouse of an album and aside from the Breckers, features a who's who of New York studio musicians including Steve Gadd, Will Lee, Don Grolnick, David Sanborn and even a pre-solo fame Luther Vandross on vocals, who must have done this album just after he did Bowie's 'Young Americans'. I would kill to get this on AF SACD for both the stereo and quad mixes - the last time this came out on CD and didn't have the dynamic range squashed was 1996! The 2007 and 2012 remasters (which were both only released in Europe) were both single digit dynamic range abominations.
(Arista also did quad mixes of Eric Carmen's first solo album (the one with 'All By Myself' on it), 3 Barry Manilow albums, 2 Melissa Manchester albums, and The Outlaws 'Lady In Waiting' but I don't know any of these albums well enough to vouch for them.)
Sincerely, the only guy in the world that owns an original Brecker Brothers 'Back To Back' promo poster: