Former Owner
- John Swyntoun1
- Joseph Anton Koch1
- Joseph Barrois10
- Joseph Whitney1
- José Antonio Conde1
- Juan de Gayferos de Eguiraum1
- Juana I of Castile1
- Julius Hess1
- Jérôme Bignon1
- Kloster Bredelar1
- Lathrop C. Harper, Inc.1
- Lathrop Colgate Harper1
- Laurence Claiborne Witten II2
- Laurentius van der Torqel1
- Leo S. Olschki Editore7
- Leonardo Lapiccirella2
- Leonello d'Este, Marquis of Ferrara2
- Libreria antiquaria Mediolanum1
- Libreria la Bibliofila1
- Louis Charles Karpinski1