Former Owner
- Josiah H. Benton1
- José Antonio Conde1
- Judith Lady Montefiore College1
- Jules Bonhomme1
- Julie de Busnel1
- Julius Hess1
- Julius de Cardelinis1
- Justin MacCarthy Reagh1
- Jérôme Bignon1
- K. B. Starkie1
- Karl Anton, Prince of Hohenzollern1
- Karl Leopold Strauven1
- Katherine Petersen1
- Katholieke Universiteit te Leuven Universiteitsbibliotheek1
- Kenneth Hyde1
- Kloster Bredelar1
- Kloster Kuringen1
- Kloster Rebdorf1
- Kulturhistorisches Museum Magdeburg1
- L. Paganthus1