Former Owner
- John Rushout, 2nd Baron Northwick1
- John Ruskin2
- John Stanley, 18th Earl of Derby1
- John William Bradley1
- Joseph Baer & Co.1
- Joseph Barrois1
- Joseph Marie Sormani1
- Joseph-Félix Allard1
- Juana Mendel1
- Julie de Busnel1
- Karl Anton, Prince of Hohenzollern1
- Karl Leopold Strauven1
- Katharinenkirche, Nuremberg1
- Lathrop C. Harper, Inc.6
- Laurence Claiborne Witten II2
- Laurence Hilliard1
- Laurence William Hodson1
- Leicester Harmsworth1
- Leo S. Olschki Editore2
- Librairie Damascène Morgand1