Former Owner
- Jacob Dackomb1
- Jacqueline du Pré1
- James & Mary Lee Tregaskis (Firm)1
- Jean-Baptiste Denis Guyon de Sardière1
- Jean-Louis Girardin de Vauvré1
- Jeremiah Styles1
- Jeronimus Maelens1
- Joachim Guerrinus de Montefegatesio1
- Joachim, Baron von Windhag1
- Johann Heinrich van Ess3
- John Boykett Jarman1
- John Eliot Hodgkin1
- John Estmond1
- John Frederick Lewis91
- John Ives1
- John Walker1
- John West, 1st Earl De La Warr1
- John Wright2
- Katholieke Universiteit te Leuven Universiteitsbibliotheek1
- Klaus Dieter Dahmen1