Former Owner
- Laura Hurd Motion1
- Leo Olschki1
- Leo S. Olschki Editore1
- Leonardus Martinotius1
- Leonhardus Cuntius1
- Leslie, John (c. 1840), bookseller1
- Librairie Tross1
- Libreria la Bibliofila1
- Louis Charles Karpinski1
- Louis H. Silver1
- Louis-Jean-Nicolas Monmerqué1
- Lucien Gougy1
- Ludovico Settala1
- Ludwig Rosenthal1
- Luigi Celotti1
- Lundell Library1
- Maggs Bros Ltd1
- Malvezzi de' Medici1
- Manuel Fernández del Castillo1
- Margaret Barclay Wilson1