Former Owner
- M. Louise Stowell1
- Mademoiselle de Malberghe1
- Magby, H1
- Mahdī ibn Muṣṭafá al-Ḥusaynī1
- Manookjee Sorabjee Ashburner1
- Manuel Fernández del Castillo1
- Manuel John Johnson1
- Marc-René de Voyer d'Argenson1
- Marie Thomas1
- Mark Lansburgh1
- Marsden J. Perry1
- Martin Schøyen1
- Marvin-L. Colker1
- Mary Stanley, Countess of Derby1
- Mary Talbot, Countess of Shrewsbury1
- Mary W. T. Dickinson11
- Mary, Queen of Scots1
- Matteo Luigi Canonici7
- Matthaeus Lupin1
- Matthew Bloxam1