The case involves a Cy Twombly work titled, "Leaving Paphos Ringed with Waves," that Perelman claims he inquired about in late April 2011 and Gagosian said the price was $8 million. When Perelman made an offer the next week for the work, he alleges that Gagosian told him it had been sold to another buyer and the new price was $11.5 million. Perelman acquired it for $10.5 million.

Perelman says he later found out the Mugrabi family was the buyer in the quick, turnaround sale. His court filings allege that Gagosian and the Mugrabis "have been working together and using both private sales and public auctions to 'inflate prices and create the appearance of trading volume.'"