Former Owner
- John Willis1
- John de Vere, 12th Earl of Oxford1
- Joseph Barrois1
- Joseph François René de Kergariou1
- Joseph Jekyll1
- Judith Lady Montefiore College1
- Jules Bonhomme1
- Katholieke Universiteit te Leuven Universiteitsbibliotheek1
- Klaus Dieter Dahmen1
- Kulturhistorisches Museum Magdeburg1
- Lady Margaret Ayloffe1
- Lambach Abbey1
- Lambertus Eerens1
- Lancino Curti1
- Lathrop Colgate Harper1
- Laura Hurd Motion1
- Laurence Kirby1
- Law Society1
- Leicester Harmsworth1
- Leonardus Martinotius1