Former Owner
- Mary Schell Collins1
- Matthias Corvinus1
- Maximilian Henry of Bavaria1
- Melk Abbey1
- Merlemont family1
- Michael Wodhull1
- Michel Chasles1
- Michel de Léon1
- Michiel family1
- Morris Jastrow, Jr.1
- Murray Anthony Potter1
- Museo Cavaleri1
- Nettie Goldsmith Naumburg1
- Neustift Abbey1
- Nicolai Briganti1
- Nicolas Fowle1
- Nicolaus de Monte Murro1
- Orlandus de Fatiis1
- Oswald Carl Friedrich von Seilern und Aspang1
- Otto Jahn1