Boolean Logic Law and Legal Definition

Boolean logic refers to the method of expressing relationships in logic arguments. The relationships are usually expressed by way of three operators -- "and", "or", "not". This logic is named after the British-born Irish mathematician George Boole.

In the context of Patent law, the patent search systems use "and", "or", and “not" as Boolean operators, in combination with parentheses. It also uses some symbols such as "->" to indicate a range, where you enter the field code and start date, ->, and then the end date. For example: ISD/2/1/1997->4/23/1998. This is for building nested logical subsets.