Former Owner
- Artemesia Piccolomini1
- Arthur Vershbow1
- Assemani family1
- Avraham Ḥai Morpurgo1
- Baldassarre Boncompagni2
- Barbarigo family1
- Bartolomeo Amici1
- Basilica of Sant'Ambrogio1
- Beatrice de Fouar1
- Beatus Rhenanus1
- Benedetto Affaticati2
- Benetto Spinelli1
- Benjamin Franklin Stevens2
- Bern Dibner1
- Bernard Quaritch Ltd7
- Bernardo Bembo1
- Bertram Ashburnham, 4th Earl of Ashburnham12
- Biblioteca Bottigella1
- Biblioteca Trivulziana1
- Breslauer and Meyer1