PARIS — Early next year, after a nearly $170 million redevelopment, Paris’s 130-year-old Bourse de Commerce will reopen as a contemporary art museum. Unlike the world-famous state-funded museums nearby against which it hopes to measure up — namely, the Louvre and the Pompidou Center — this one will be financed by one man: the French billionaire François Pinault, whose collection consists of about 5,000 works by artists such as Jeff Koons, Cy Twombly, and Cindy Sherman.

Mr. Pinault, 82, is the founder of the company that eventually became the Kering luxury-goods group. His family holding company also controls the auction house Christie’s, among several other assets . He already has two exhibition venues in Venice. Now he’s transforming the Bourse — a circular exchange building where wheat, sugar and other commodities were once traded — into the latest and most conspicuous vitrine for his collection.