The case of the alleged Marilyn Monroe erotic film that failed to sell at auction in Argentina over the weekend is a fascinating lesson on the art market. In this world, sex doesn't sell — authentication does.

Just a few weeks ago, ARTINFO reported that an 8mm take from a 1947 blue movie supposedly staring the actress would be sold at auction in Argentina by Spanish memorabilia collector Mikel Barsa. He said that the bidding would start around $500,000, and that he hoped it would fetch around $1 million. But the Associated Press reported this morning that the film failed to reach even its minimum bid.

This is likely because the assertion that the woman in the video is actually the famed star is difficult to prove. Barsa has two documents that he says authenticate that it is her: a statement from the American Film Institute stating that it's either her or a very good loo-alike, and a declassified FBI document which reveals that Monroe's ex-husband Joe DiMaggio tried to buy the tape from the FBI for $25,000 after her death.

Nancy Carlson, a spokesperson from the estate of Marilyn Monroe, went on the record with the AP last week calling the video a fraud, which probably deterred buyers. By yesterday's auction date, Barsa himself said he was not surprised that the video failed to fetch even the minimum bid. In addition to calling the video a fraud, Carlson threatened legal action for violation of Monroe's intellectual property rights. Half a million plus a lawsuit is apparently too high a price to pay for disputed vintage celebrity porn.