Former Owner
- Ohio State University Center for Epigraphical and Palaeographical Studies1
- Ohio State University School of Music1
- Okar, Baganbhaṭṭa1
- Omaha Public Library1
- Orlandus de Fatiis1
- Otto Haas1
- Otto Jahn1
- Otto Orren Fisher1
- Owen D. Young1
- P. Desq1
- P. J. De Mat1
- P. Pigeot1
- PBA Galleries1
- Pandit Gobindpurshad1
- Pangracius Chrewczer1
- Paolo Gallo1
- Paolo Guerrini1
- Parish Church of St. John the Baptist1
- Parish Church of Waldhausen im Strudengau1
- Park Abbey1