Sarah Douglas has the details from Jack Tilton’s testimony in the Robins v. Zwirner suit over Marlene Dumas’s blacklist on ArtInfo.com:

In detailed testimony, Tilton explained his knowledge about how the list was administered and revealed prominent names that were on the list, including major collectors (like Richard Cooper and Daniel Holtz), dealers (like Marc Jancou), and David Zwirner, who began representing her in 2008. [….]

The irony is that Tilton’s testimony, secured via subpoena by the Robins camp — presumably to bear witness to the fact that Zwirner had informed Dumas of Robins’ sale of Reinhardt’s Daughter — suggested that Tilton himself may have actually told Dumas about Robins’ sale of that painting. It also emerged from Tilton’s testimony that Tilton proposed Zwirner’s name be added to the blacklist.

Tilton Confirms Dumas Blacklist Included Prominent Collectors, Dealers, and . . . David Zwirner (ArtInfo.com)