Former Owner
- Baldasarre Boncompagni1
- Baptist Union Theological Seminary1
- Bartolomeo di Larione Martelli1
- Battle Abbey1
- Benoît Le Court1
- Bern Dibner1
- Bernard Quaritch Ltd1
- Betty Freudenheim1
- Bibliotheca Beggadorum1
- Bibliotheca Philosophica Hermetica1
- Bill Jackson1
- Brayton C. Ives1
- Bruce P. Ferrini1
- Budapest University of Jewish Studies1
- Burg Kreuzenstein1
- C.B1
- Caesareum Societatis Jesu Collegium Viennense1
- Carleton Rubira Richmond1
- Carlo Archinto, 2nd Marquess of Parona, 3rd Count of Trainate1
- Carlo Bonaparte1