Former Owner
- John Leeche1
- John Lumley, 1st Baron Lumley1
- John R. Anderson & Co1
- John Roland Abbey1
- John Ruskin1
- John Savile1
- John Taylor1
- John Thomas Beer1
- John Towneley1
- Joseph Ernst Koch-Sternfeld1
- Joseph Pope1
- Joseph-Félix Allard1
- Juan Burgueño1
- Juan de Gayferos de Eguiraum1
- Juana I of Castile1
- Julian Burgueño1
- Julius de Cardelinis1
- Jérôme Bignon1
- Karl Hermann Berendt1
- Kenneth X. Robbins1