Former Owner
- Jérôme Bignon1
- K-L1
- K. B. Starkie1
- Karl Anton, Prince of Hohenzollern1
- Karl Leopold Strauven1
- Katherine Petersen1
- Katholieke Universiteit te Leuven Universiteitsbibliotheek1
- Kenneth Hyde1
- Klaus Dieter Dahmen1
- Kloster Bredelar1
- Kloster Kuringen1
- Kulturhistorisches Museum Magdeburg1
- L. C. Harper1
- L. Paganthus1
- Lady Margaret Ayloffe1
- Lajos Graf Apponyi de Nagy-Appony1
- Lancino Curti1
- Lane Theological Seminary1
- Latham family1
- Laura Hurd Motion1