Former Owner
- M. Haimmiller1
- Magby, H1
- Margaret Barclay Wilson1
- Margaret of Croy1
- Marie Cleophe de Sollario1
- Marie de Albano1
- Marienstiftsgymnasium1
- Mark Lansburgh1
- Mary Augusta Strachey1
- Mary Schell Collins1
- Matteo Barresi1
- Matthew Bloxam1
- Matthew Simpson Parkhurst1
- Matthias Corvinus1
- Maurice Johnson1
- Maximilian Henry of Bavaria1
- Melk Abbey1
- Michael Tomkinson1
- Michaeliskonvent1
- Michel Chasles1