Former Owner
- John Gunthorpe1
- John Henry Ellis1
- John Lee1
- John Morgan1
- John Rolls, 2nd Baron Llangattock1
- John Rushout, 2nd Baron Northwick1
- John Ruskin1
- John Stanley, 18th Earl of Derby1
- John Thomas Beer1
- John Walker1
- John William Burns1
- Joseph E. Widener1
- Josiah H. Benton1
- Juana Mendel1
- K-L1
- Karl F. Morrison1
- Keith Jarvis1
- Laurence Claiborne Witten II1
- Laurence William Hodson1
- Lehn of Denmark1