Former Owner
- Paul Riant1
- Peter Le Neve1
- Petrus Hofstede1
- Philadelphia Rare Books & Manuscripts Company1
- Philip C. Duschnes1
- Philip Hofer1
- Philip Kerr, 11th Marquess of Lothian1
- Philippe de Béthune1
- Phillip J. Pirages Fine Books & Manuscripts1
- Québriac family1
- R. A. Godwin-Austen1
- R. Stora and Company1
- Raoul Léonor Lignerolles1
- Renzo Rizzi libri antichi1
- Rev. Frederick Collins Wilson1
- Ricardo, Conde de Benahavis Heredia1
- Robert Forrer1
- Robert de Hangest1
- Rudolf Busch1
- Rush Hawkins1