Former Owner
- John III of Portugal2
- John Ives2
- John Patrick Auguste Madden2
- John Rolls, 1st Baron Llangattock2
- John Thomas Beer2
- John Topham2
- John Wallop, Viscount Lymington2
- John Wright2
- Joseph Haslewood2
- Joseph L. Lilly2
- Josephine Widener Wichfield2
- Jérôme Pichon2
- Karl F. Morrison2
- Kartause Erfurt2
- Kenneth J. "Bud" Jennings2
- Kloster Rebdorf2
- Lane Theological Seminary2
- Leonardo Lapiccirella2
- Leopold Gruber2
- Lew David Feldman2