The definition of 'B shares'

Classes of shares with specific sets of rights that are are defined by the company’s articles of association. These shares typically offer investors rights and benefits that decrease in alphabetic order, B shares offering less than a shares, C shares offering less than B shares, and so on.

It is imperative that investors read all of the rights their share class affords as some share classes will not offer investors voting rights, pre-emption, or other key investor protections.