Former Owner
- Maria Riddell1
- Mario Maffei1
- Markus Fugger1
- Mary Augusta Strachey1
- Mary Schell Collins1
- Matteo Luigi Canonici3
- Maximilian Henry of Bavaria1
- Mayer Sulzberger2
- Mazliah Finzi1
- Maḥmūd bin Nāṣir1
- Melk Abbey1
- Michael Bernays1
- Michel Chasles1
- Michel de Léon1
- Mitchell Starrett Buck1
- Mobed Framji Fardunji Madan1
- Mobed Hormazdyar Mobed Khodabaksh1
- Mohammed bin Hamed bu Osman1
- Monastero di Santo Spirito in Verona1
- Monteles, Avraham de1