David Tunick, a New York dealer, and Eberhard Kornfeld, a Swiss auctioneer, will see each other in court. Mr Tunick is seeking refund on the price he paid for the Picasso and punitive damages of dollars 20m (pounds 13m); Mr Kornfeld is suing for outstanding payment.
Their quarrel concerns the authenticity of the pencil signature on an impression of Picasso's famous 1935 print La Minotauromachie - the mythical half-man, half-bull. The two have locked horns over that signature since 1991, when Mr Tunick exhibited the print at the annual Art Show in Manhattan. Although it had pride of place on his stand and a price tag of dollars 2m, it did not sell.
Eight months later, and 16 months after purchasing it, Mr Tunick said experts had questioned the authenticity of the signature, but not the print. A signed print is significantly more valuable.
Mr Kornfeld, a Picasso expert, offered to exchange it for a copy of the same print in his private collection - a version that had for years been on loan to the Museum of Modern Art in New York. According to Jeremy Epstein, of Shearman & Sterling - Mr Kornfeld's lawyers - Mr Tunick refused the swap and demanded his money back.
In October 1991, nine days after Mr Tunick claimed he had discovered that the print's signature was fake, he sued Mr Kornfeld in the US Federal District Court in Manhattan. He cited fraud, breach of warranty and wreckless misrepresentation.
A month later, Mr Kornfeld filed a lawsuit in Switzerland for the money he was still owed. In December 1992, the case was dismissed in the Swiss courts on jurisdictional grounds and, after appeal, that ruling was affirmed three months ago.
In January this year, the Federal District Court in Manhattan ruled that the case would proceed in New York.
In July this year, Mr Kornfeld filed a counter-claim against Mr Tunick in New York, suing for breach of contract and fraud, to recover the balance of the amount. Both sides moved to dismiss the other's claims, but the judge denied the motions. The case is likely to come to court within the next few weeks.