The piece was put up for sale by a man who identified himself only by the user name "golfpoorly."
"I got this big abstract art painting at a garage sale in Berkeley ... back in my bachelor days," he wrote in his description of the piece. "Then I got married, and my wife has never let me keep it in the house. She says it looks like it was done by a nutcase."
He didn't say who might have painted it.
But art experts said the photo shown on eBay shows some of the techniques of abstract expressionism that the late Richard Diebenkorn worked with in 1952. And a blowup of a tear in the painting showed the signature "RD," the way Diebenkorn typically signed his work.
The top bid before the eBay auction closed was entered by a man identified as Rob Keereweer of the Netherlands, the The New York Times reported Tuesday.
Keereweer could not be located in the Netherlands by The Associated Press.
Diebenkorn, who died in 1993, was born in Portland, Ore., and spent the later part of his life in California. He switched styles twice, but spent the last 25 years of his working life painting mostly lines and geometric forms in the brilliant colors that had become his trademark.
The record price for a Diebenkorn at auction was $3.9 million, bid in 1998 at Sotheby's for a painting titled "Horizon: Ocean Park."
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