co-owner

• coowner

co- +‎ owner.

co-owner (plural co-owners)

1. Someone who owns something together with one or more other people.
   • 1988, February 5, “Achy Obejas”, in The Press: Averting Our Gays‎:

     […] when a gay man really does die of something other than AIDS, as in the case of Tom Norton, the popular coowner of Unabridged Books, festering doubt will plague his memory.

• joint owner

• co-ownership

• “co-owner” (US) / “co-owner” (UK) in Oxford Dictionaries, Oxford University Press.