IP address filtering can have two distinct meanings in digital marketing and advertising context.
First, it can be understood as IP address blocking.
Second, it can mean to give a special treatment to visitors or visits originating from specific IP addresses - or ranges of IP addresses. For instance bot traffic can be authorized to access a website but not taken into account for determining traffic statistics or foreign IP adresses be redirected to another domain.
IP address filtering is also a key component of email spam filtering arsenal.