Former Owner
- Mercantile Library Company1
- Merlemont family1
- Meschatin La Faye family1
- Michael Wodhull1
- Michaeliskonvent1
- Michel Chasles1
- Michel Ferdinand d'Albert d'Ailly1
- Michel Guibé1
- Michel de Léon1
- Michiel family1
- Mikhail Golitsyn1
- Millard Meiss1
- Minerva Kaiser1
- Mirmellus Arnandi1
- Molin1
- Monasterium sanctorum quadraginta martyrum (Treviso Italy)1
- Monastery of Benevívere1
- Monastery of Saint Peter (Erfurt, Germany)1
- Monastery of San Bartolmeo, Arezzo, Tuscany1
- Monica Franklyn1