because corporation members were usually "in the pocket" of a wealthy patron);
# Boroughs in which male householders were electors (these were usually known as "potwalloper boroughs", as the usual definition of a householder was a person able to boil a pot on his/her own hearth);
# Boroughs in which freeholders of land had the right to vote.

Some boroughs had a combination of these varying types of franchise, and most had special rules and exceptions, so many boroughs had a form of franchise