Former Owner
- J. Martini1
- J. Paul Getty Museum1
- J. Thomson1
- Jacob Henry Burn1
- Jacob Riegel1
- Jesuit College of San Bartolomeo1
- Johannes Baptista Siccus1
- John Bolton1
- John C. Jackson1
- John D. Stanitz1
- John Lee1
- Julie Florence de Cossette1
- Katherine Somerset Wyttenbach Fenwick1
- Lathrop C. Harper, Inc.1
- Leo Olschki1
- Lorenzo Antonio da Ponte1
- Luigi Celotti1
- Luigi Cora1
- M. Favia del Core1
- Maggs Bros Ltd1