A London-based art dealer asked the New York Court of Appeals on Monday to hear his claim to a pair of century-old drawings by Austrian artist Egon Schiele, arguing that lower state courts’ decisions would upend the New York art world if they were allowed to stand.

William Charron of Pryor Cashman, who is representing dealer Richard Nagy, argued that an earlier federal court case settled questions about rightful ownership of the drawings, which are part of a collection owned by a Jewish Austrian collector, Fritz Grunbaum, in the 1930s.