Former Owner
- Joseph E. Widener1
- Judith Lady Montefiore College1
- Lancino Curti1
- Lathrop Colgate Harper1
- Laura Hurd Motion1
- Leonardus Martinotius1
- Leonello d'Este, Marquis of Ferrara1
- Lodovicus Saltariellus1
- London School of Jewish Studies1
- Louis Bourguet1
- Louis XII of France1
- Luigi Cora1
- Luini, Pacifico (Franciscan priest), active 19th century1
- Maggs Bros Ltd1
- Marchese Porri-Carcani1
- Mario Maffei1
- Martin Breslauer1
- Mercantile Library Company1
- Monastero di Santo Spirito in Verona1
- Moritz Dessauer1