Scott Reyburn does a strong job of outlining the forces and players behind the rise of Kazuo Shiraga’s market:

Shiraga’s resurgence is helped by the vogue for so-called process-based abstraction, and a revival of interest in performance art. Shown by the Belgian dealer Axel Vervoordt next to European postwar abstracts by Luciano Fontana and Zero group artists at the Venice Biennale beginning in 2007, his paintings were a revelation to American tastemakers like the Dallas collector and philanthropist Howard Rachofsky and Ms. Lévy, the New York gallerist.

“When you saw it in context with Fontana, there was a degree of interaction; it was a quick and easy leap,” said Mr. Rachofsky, a former hedge fund manager who has a private museum and is one of the world’s most prominent collectors of American minimalism and Italian postwar art. “There’s a lot of spirit in these paintings.”

In recent years, Mr. Rachofsky, with his adviser, Allan Schwartzman, and Mr. McCaffrey, has regularly traveled to Japan, quietly amassing a collection of about 40 works by Shiraga and other Japanese conceptually minded artists that complemented his holdings of American and European art.

Art World Rediscovers Kazuo Shiraga  (NYTimes.com)