Deep in Bloomberg’s recap of the Rybolovlev-Bouvier saga—where neither side comes out looking good—is the story of perhaps the greatest art deal ever. Bouvier convinced Rybolovlev to buy Mark Rothko’s No. 6 for €140m which surpasses even the price paid for Bunny Mellon’s No. 20 (Yellow Expanse) when it sold privately for $150m.

Bouvier potentially compounded the €80m gain on the Rothko by adding a Modigliani as payment in kind. Unfortunately, this last over-sized deal was the one that Bouvier refused to consummate fully and became the pretext for luring Bouvier to Monaco for the oligarch’s sting:

In the summer of 2014, as he was gearing up for the Luxembourg opening, Bouvier presented Rybolovlev with an opportunity to buy a work by one of America’s most important postwar artists: Mark Rothko. Christie’s had sold his Orange, Red, Yellow at auction for a record $87 million in 2012. Bouvier had found a private collector who wanted to sell No. 6 (Violet, Green and Red), one of the abstract impressionist’s most famous works. He began negotiating with Rybolovlev on the price.

After some back and forth, the two men settled on €140 million, making it one of the most expensive paintings ever sold. Rybolovlev agreed to sell a Modigliani sculpture, Tête—which he’d bought via Bouvier in 2012—for €60 million as a partial payment for the Rothko. “I convinced the seller of the importance of Tête by Modigliani, and he agrees to take it in part exchange for 60m euros,” Bouvier wrote to Sazonov on Aug. 4, 2014, the complaint says.

Unknown to Rybolovlev, the seller of the Rothko was Cherise Moueix, the wife of Christian Moueix, a French winemaker who oversees Château Pétrus. She declined to comment. Bouvier told the Monaco prosecutor that he bought the Rothko from Moueix through an intermediary for $80 million plus an unspecified commission—roughly €80 million less than the Russian agreed to pay at the time.

The Singapore court, meanwhile, has put No. 6 under judicial supervision; its exact whereabouts haven’t been disclosed. Bouvier says Rybolovlev still owes him about $40 million for the painting, based on the agreed price. Rybolovlev has refused to pay the balance, saying he’s already shelled out more than the $80 million Bouvier paid.

A $186 Million Rothko Pits Russian Tycoon Against Art Merchant (Bloomberg Business)