Former Owner
- Joseph L. Lilly1
- Joseph Mayner1
- Juan Burgueño1
- Judith Lady Montefiore College1
- Julian Burgueño1
- Kenneth Hyde1
- Konrad von Maurer2
- Lancino Curti1
- Laurence Claiborne Witten II1
- Laurence Kirby1
- Law Society1
- Lawrence J. Schoenberg15
- Leicester Harmsworth1
- Leo Olschki2
- Leonard Grey, 1st Viscount Grane1
- Levi, David, active 19th century1
- Lindwer, Willy2
- Lionardo di Paolo Adimari1
- Llewelyn Lloyd-Mostyn, 3rd Baron Mostyn of Mostyn2
- Lodovicus Saltariellus1