In 1951 Jacques Seligmann & Co., Inc., negotiated to sell the private family collection of the Duc d'Arenberg. Collection items under Seligmann's care included nineteen illuminated manuscripts and three paintings: Jan Vermeer's Antoine Watteau's and Rembrandt van Rijn's This subseries documents the activities undertaken by the firm in carrying out the sale of the collection through correspondence and contracts, along with details of financial and legal actions taken pertaining to the sale and transfer of collection items. The subseries also contains historical information and reference files for items in the collection.

Material is arranged in chronological order under subject headings. The bulk of this series has been scanned with the exception of some printed material.