John B. Ladd was an art collector and businessman (with his brother-in-law, Sturgis Coffin, founded the perfumes house of Ladd & Coffin).
Ladd’s collection included work by, among others, Jean B. C. Corot, Mantes, Van Marke, Jacque, Israels, Anton Mauve, Eugene Ciceri, Cazin, Corot, A. Pasini, George Inness, Jules Dupré, A H Wyant, Horatio Walker, Arthur Quarterly, Santoro, E. Berne-Bellecour, F. Dielman, Leonard Ochtman, Hugo Kaufman, Seignac, Carl Sierig, E. Grison, Sanchez-Pierrier, Pelouse, Jacomin, Jean Beraud, J. A. Walker, Albert Neuhuys, Raffaelli, Boudin, and Paul Burmeister.
In addition to paintings by the artists listed above he owned water colors of the Dutch School, etchings and Chinese porcelains.
Ladd was a member of the Brooklyn Institute (now known as the Brooklyn Museum of Art), and the Rembrandt and Union League clubs of New York City.