Former Owner
- John C. Jackson1
- John Camp Williams1
- John Couch Adams1
- John Edgar Ker1
- John Henry Nash1
- John Hope, 1st Marquess of Linlithgow1
- John Lee1
- John Roland Abbey1
- John Ruskin1
- John Shelton Lawrence1
- John Thomas Beer1
- Joseph Barrois1
- Joseph Pope1
- Juan Antonio de la Reguera1
- Juan de Aillon1
- Juan de Torquemada1
- Judith Lady Montefiore College1
- Julius de Cardelinis1
- Katherine Somerset Wyttenbach Fenwick1
- L. Paganthus1