With private transactions constituting an essential and increasingly profitable business segment, through the years Sotheby's has bought art galleries and helped dealers finance purchases. It has also gone into partnership with dealers on private sales. In 1990, Sotheby's teamed up with dealer William Acquavella, to form Acquavella Modern Art, a Nevada general partnership and a subsidiary of Sotheby's Holding Company. The subsidiary paid $143 million for the contents of the Pierre Matisse Gallery in Manhattan, which included about 2,300 works by such artists as Miró, Jean Dubuffet, Alberto Giacometti, and Marc Chagall, and began selling the works both at auction and privately. In 1996, Sotheby's acquired Andre Emmerich Gallery to operate a division called Emmerich/Sotheby's, and in 1997 it purchased a 50% interest in Deitch Projects. As a consequence, the Josef and Anni Albers Foundation, the main beneficiary of the artists' estates, as well as the estates of Morris Louis and Milton Avery announced that they would not renew their Emmerich contracts. That decision came right after it was disclosed that Sotheby's had decided to close Emmerich's prime space at 41 East 57th Street, and that its artists would be handled out of Deitch Projects. Sotheby's subsequently closed Andre Emmerich in 1998 and later sold its share in Deitch Projects back to Jeffrey Deitch. In 2006, Sotheby's acquired a Dutch dealership, Noortman Master Paintings, from its owner, Robert Noortman, for $82.5 million ($56.5 million worth of Sotheby's stock and assumption of more than $26 million in gallery debt, including $11.7 million owed to the auction house). Sotheby's and Noortman had collaborated before in 1995, when the sales of Dutch plastic millionaire Joost Ritman were divided between the two companies.