N argument could be made that Katz is as historically important as friends like David Hockney (whose public sale record is $91 million) and Gerhard Richter (whose auction report is $46.3 million)—and yet his market has lagged behind theirs. Ropac’s first present of Katz’s work in Paris within the early ’90s “was a complete surprise to many Europeans, together with museum curators,” he stated. The Centre Pompidou, which held works by American friends like Jasper Johns but not one by Katz, purchased one. And the fever spread, as Ropac mentioned; at last rely he’d bought virtually 50 pieces to European …