Former Owner
- Maurice Kann1
- Maxwell Sommerville1
- Mayer Sulzberger1
- Mayfair Rare Books and Manuscripts1
- Maḥmūd bin Nāṣir1
- Melk Abbey1
- Menaḥem Naḥum, ha-Leṿi, mi-ḳ.ḳ. Dribin1
- Meschatin La Faye family1
- Michael Kantakouzenos Şeytanoğlu1
- Michael Wodhull1
- Michaeliskonvent1
- Michel de Léon1
- Michele Amari1
- Middle Hill Rare Books & Manuscripts AB (Stockholm, Sweden)1
- Millard Meiss1
- Minerva Kaiser1
- Minnis, Katherine1
- Mirmellus Arnandi1
- Molin1
- Monasterium sanctorum quadraginta martyrum (Treviso Italy)1