Former Owner
- Otto Ege1
- Otto Jahn1
- Otto Orren Fisher1
- P. Desq1
- Philip Augustus Hanrott1
- Philippe II de Croÿ1
- Phillip J. Pirages Fine Books & Manuscripts1
- Phoebe Hearst1
- Piero Ginori Conti1
- Pierre Tassel1
- Prince Augustus Frederick, Duke of Sussex1
- Raoul Chandon de Briailles1
- Raoul Léonor Lignerolles1
- Raymond Oliver1
- Richard Heber1
- Richard McKeon1
- Richard N. Frye1
- Robert Dallas1
- Robert Mignan1
- Robert Samuel Turner1