Former Owner
- Karbalāʼī Muḥammad Ḥusayn Qāsimʹābādī1
- Katholieke Universiteit te Leuven Universiteitsbibliotheek1
- Khouri, Elias Alexander1
- Kloster Kuringen1
- Lady Margaret Ayloffe1
- Lambertus Eerens1
- Laurence Claiborne Witten II1
- Laurent Campagne1
- LeMare1
- Legoué1
- Leonardus Martinotius1
- Lepeletier de Rosanbo1
- Librairie Tross1
- Library of the Dominicans of Paris1
- Lionel Tollemache, 4th Earl of Dysart1
- Lisa Norris Elkins1
- Llewelyn Lloyd-Mostyn, 3rd Baron Mostyn of Mostyn1
- Lodovicus Saltariellus1
- Louis Bourguet1
- Louis César de La Baume Le Blanc1