Former Owner
- Julius Hess1
- Julius de Cardelinis1
- Justin MacCarthy Reagh1
- K-L1
- Karl F. Morrison1
- Katholieke Universiteit te Leuven Universiteitsbibliotheek1
- Keifer1
- Klaus Dieter Dahmen1
- Kloster Rebdorf1
- Kulturhistorisches Museum Magdeburg1
- Lady Margaret Ayloffe1
- Lajos Graf Apponyi de Nagy-Appony1
- Lambertus Eerens1
- Lancino Curti1
- Latham family1
- Laura Hurd Motion1
- Laurence Kirby1
- Laurentius van der Torqel1
- Law Society1
- Lehn of Denmark1