Domenico De Sole, chairman of Tom Ford International, and his wife Eleanore, have sued Michael Hammer, chairman of the defunct Knoedler Gallery, over a fake Mark Rothko.

One of four pending suits against the gallery and its former staff, the De Soles amended their complaint in Manhattan federal court last week.

Hammer and Glafira Rosales, the supplier of a host of allegedly forged artworks, gallery employee Jaime Andrade, and Rosales' companion Jose Carlos Bergantinos Diaz were added to the complaint which also includes Ann Freedman, the former gallery director.

Plaintiffs are seeking damages of more than $70 million for the fakes they say Knoedler knowingly sold them.

Hammer is the grandson of Armand Hammer, the former chief executive of Occidental Petroleum Corp., and he nows runs the Armand Hammer Foundation.