Former Owner
- James & Mary Lee Tregaskis (Firm)2
- James Bowen2
- Jay Gould2
- Jean-Baptiste Denis Guyon de Sardière2
- Johan Meerman2
- John Boyd Thacher I2
- John Egerton, 1st Earl of Bridgewater2
- John Egerton, 2nd Earl of Bridgewater2
- John Egerton, 3rd Earl of Bridgewater2
- John III of Portugal2
- John Lee2
- John Roland Abbey2
- John Thomas Beer2
- Josephine Widener Wichfield2
- Karl F. Morrison2
- Kenneth J. "Bud" Jennings2
- Kloster Rebdorf2
- Lambach Abbey2
- Leonardo Lapiccirella2
- Librairie Damascène Morgand2