The Australian bank account number itself is not sensitive, but identifies a bank account, without identifying the bank branch. Therefore, both the account number and branch information must exist for the document to be considered sensitive.
The content blade looks for matches to both:
An Australian bank account number
Words and phrases related to bank state branch or BSB.
It also uses a regular expression rule to differentiate between telephone numbers of the same length.
An Australian bank account number is 6 to 10-digits without any embedded meaning. It has no check digit routine.