Former Owner
- Oliver R. Barrett1
- Oswald Carl Friedrich von Seilern und Aspang1
- Otto Orren Fisher1
- Otto Vollbehr1
- P. J. De Mat1
- Pascal Gay1
- Paul Durrieux1
- Paul Gottschalk1
- Payre-Grolée-Virville family1
- Peter Arrell Brown Widener1
- Petrus Giraud1
- Petrus Hofstede1
- Philadelphia Rare Books & Manuscripts Company1
- Philibert-Charles-Marie Varenne de Fenille1
- Philip C. Duschnes Rare Books & First Editions1
- Philip Hurd1
- Philip Kerr, 11th Marquess of Lothian1
- Philip Sills1
- Philippe Hurault de Cheverny1
- Philippe de Béthune1