The Calder Foundation has prevented the sale of an Alexander Calder sculpture worth an estimated $1.2 million, claiming the mobile, Eight Black Leaves, is a fragment of a larger work. Swiss art dealer Patrick Cramer, whose father bought the work from the artist himself in 1948,  has filed against the Calder Foundation in federal court, seeking damages to the tune of $3.6 million.

Cramer attempted to sell Eight Black Leaves at Christie’s in April 2012, but the Foundation would not issue the sculpture an inventory number, which is necessary for any sale, despite recognizing the authenticity of the piece. The dealer has accused the Calder Foundation of attempting to control “the market for Calder works through arbitrary determinations of authenticity.”