Former Owner
- Mary W. T. Dickinson11
- Mary, Queen of Scots1
- Marāṭha, Raṅganātha1
- Mathias Schurer1
- Matteo Barresi1
- Matteo Luigi Canonici20
- Matthaeus Lupin1
- Matthew Bloxam1
- Matthew Donadski1
- Matthew Hale1
- Matthew Simpson Parkhurst1
- Matthias Corvinus1
- Mauni, Bālaṃbhaṭa1
- Maurice Johnson1
- Maurice Kann1
- Maurilio Morazio1
- Maximilian Henry of Bavaria1
- Maxwell Sommerville1
- Mayer Sulzberger5
- Mayfair Rare Books and Manuscripts1