William Moulton IV was part of a large family of silversmiths that spanned several generations and that worked primarily in Newbury, Newburyport, and Boston, Massachusetts.  His grandfather and father were silversmiths; at least two brothers also entered the trade. 

Later in the 19th century, the firm then in the possession of Joseph Moulton (1814–1903), a grand-nephew of Ebenezer (William’s brother), was sold to Anthony Francis Towle and William P. Jones, who formed the forerunner to the present-day firm of Towle Silversmiths.