Former Owner
- Boudewijn Willemszoon van Drenckwaert1
- Branners Bibliofile Antikvariat1
- Brayton C. Ives3
- Brick Row Book Shop1
- Bridget Hunt1
- Bruce Bannerman1
- Bruce P. Ferrini9
- Brudenell family1
- Budapest University of Jewish Studies1
- Burg Kreuzenstein1
- Burgersdijk & Niermans1
- Burndy Library3
- Buxheim Charterhouse9
- C.B1
- Caesareum Societatis Jesu Collegium Viennense1
- Camillo Riccio1
- Carleton Rubira Richmond1
- Carlo Archinto, 2nd Marquess of Parona, 3rd Count of Trainate3
- Carlo Bonaparte1
- Carlo Francesco Frasconi1