Former Owner
- John Walker1
- Joseph E. Widener1
- Juan de Aillon1
- Juan de Torquemada1
- Judith Lady Montefiore College1
- Julius Hess1
- Katherine Petersen1
- Kenneth Hyde1
- Lajos Graf Apponyi de Nagy-Appony1
- Lancino Curti1
- Lathrop C. Harper, Inc.1
- Laura Hurd Motion1
- Leonardo Bruni1
- Leonardus Martinotius1
- Leonhardus Cuntius1
- Leopold Gruber1
- Libri, Edoardo, active 20th century1
- Llewelyn Lloyd-Mostyn, 3rd Baron Mostyn of Mostyn1
- Lodovicus Saltariellus1
- Louis Bourguet1