In law, a joint owner or tenant in common, who has an independent, although an undivided, interest in property with another or others.(noun)
The Century Dictionary (Public Domain)
Use "part-owner" in a sentence
"Redskins minority owner Robert Rothman and part-owner Dwight Schar each contributed $5,000."
"Hillwood contends that as a part-owner of the Mavericks, the rich spending "has substantially diminished" the value of its investment."
"In December 2003, Bruce Ratner, a real estate tycoon and part-owner of the New Jersey Nets basketball team, held a press conference in New York City to announce his latest project, a 22-acre "urban utopia" called the Atlantic Yards."