Former Owner
- John Sidney Hawkins1
- John Stirton1
- John Stow1
- John Taylor1
- Joseph Barrois1
- Joseph H. Haines1
- Joseph Jekyll1
- Juan de Gayferos de Eguiraum1
- Julia Burgess2
- Julian I. Edison1
- Julie Florence de Cossette1
- Justin MacCarthy Reagh1
- Kaikhusroo Minocher Jamaspasa1
- King Lawrence Parker1
- Klaus Dieter Dahmen1
- Laurence Vaux1
- Leonello d'Este, Marquis of Ferrara1
- Long Island Historical Society, Maine1
- Louis César de La Baume Le Blanc2
- Louis Herbert Gray1