In a major embarrassment on the eve of the Chinese fall auction season, a painting sold at auction last year for RMB 72.8 million ($11.4 million) as a masterpiece by Chinese modern master Xu Beihong (1895-1953) has been denounced as a fake.                                

The painting — listed as an oil-on-canvas nude study of the artist's wife, Jiang Biwei, painted in the 1920s — was knocked down for a multi-million dollar price at the Beijing Jiuge International Auction House last June. Jiuge was recently named by France's Conseil de Ventes as one of the top 20 auction houses in the world by auction turnover.

The painting was authenticated for the house by Xu Beihong's elderly son Xu Boyang in September 2007, and a photo of him with the painting as well as his letter of authentication was part of the documentation provided to bidders at last Summer’s auction.

However, according to an open letter published late last week by ten former oil painting students of Beijing's Central Academy of Fine Arts (CAFA), the painting was in fact created by one of their classmates as a part of a "class exercise" in 1983, thirty years after the painter's death. The former students say they are not sure which one of their class of twenty actually painted the work but it was definitely one of the canvases produced in 1983 as part of a three-week class exercise in copying the "classic realist" style of Xu Beihong and his early twentieth century peers. Far from being a portrait of the artist’s wife, they say, the subject was a professional figure-drawing model from a rural area of the eastern province of Jiangsu.

Those who can throw most light on the mystery seem to have gone to ground. According to a report in the Global Times (the English language tabloid sibling of the Communist Party's official organ People's Daily), Jiuge would not comment on the students' claims, and the China Daily newspaper reported that attempts to reach Xu Boyang, who lives in Hong Kong, were unsuccessful.

Experts quoted across the Chinese media threw further doubt on the authenticity of the work. Tsinghua University scholar Lü Lixin said a comparison of photographs of Jiang Biwei with the painting indicated that she was not the subject. Meanwhile in an interview with China National Radio, respected artist Chen Danqing was scathing about the painting: "It is not even fair to call it a fake," he said. "A forger would actually attempt to imitate Xu's work. This one has no similarity with Xu's style." Chen went on the record as saying he believed the painting had been "deliberately misrepresented" as Xu's work.

As yet nothing has been heard from the unlucky buyer, who on the face of it has paid almost 11 and a half million US dollars for a painting by a nonentity, but commentators have already pointed out that opportunities for redress are quite limited.

Auction houses in China are not legally allowed to make claims of authenticity for the works they sell, which has been interpreted by some as exempting them from responsibility in disputes over authenticity. But the auction industry's own rules say that compensation should be paid if "at least three experts" agree that a work sold at auction is counterfeit. However, what the quantum of any compensation should be is not specified. The whole case also points up the lack of any established system of authentication in China for art works.

Xu Beihong was ranked at number 6 on Artprice's top ten artists by auction value last year, with sales totalling $176.3 million. A highly respected and influential figure in Chinese modern painting, Xu is best known for his works of ink on paper — most notably of horses — which attempted to introduce Western notions of perspective and composition into traditional Chinese painting. Xu was also a pioneer in the use of oil on canvas in the early part of the twentieth century, having joined a wave of progressive young Chinese artists who travelled to Paris in the 1920s to study Western art.

Works by Xu figure prominently on the slate of a number of leading auction houses during this coming fall season, including Sotheby's Hong Kong. The first ever retrospective of Xu Beihong in North America is due to open on October 30 at the Denver Art Museum.