Former Owner
- Jean Joseph Sosthène de LaRoche Lacarelle1
- Jesuit College of San Bartolomeo1
- Joachim Guerrinus de Montefegatesio1
- Joannes Salzperg1
- Johann Heinrich van Ess1
- Johannes Betrus Ravenoldus1
- Johannes Wesbach1
- Johannes, de Sancto Nabore1
- John Carter1
- John Edgar Ker1
- John Frederick Lewis1
- John Henry Nash1
- John Hunt1
- John Jarsey1
- John Lee1
- John Roland Abbey1
- John Rolls, 1st Baron Llangattock1
- John Ruskin1
- Joost Ritman1
- Karen L. Gould1