 In September 2008, Yeghiayan filed suit against the National Archives and Records Administration of the United States, seeking documents from 1914 to 1925 relating to the Armenian Genocide, following the administrations failed response to his repeated request to procure information.In June 2010, Yeghiayan filed on behalf of the Western Prelacy of the Armenian Church suit against the J. Paul Getty Museum for the return of eight thirteenth-century Armenian illuminated manuscript folios, the work of Armenian manuscript illuminator Toros Roslin, the first such case in the United States that the return of cultural or religious objects stolen during the Armenian Genocide.In September 2015 both parties reached an agreement whereby legal title of the folios would be returned to the Church while the pages themselves would remain in the possession of the Getty.