Licensing revenue is a good indicator of that, in part because licensing suggests that someone's paying you for the use of the intellectual property, which means it's actually in application. In terms of the degree to which you can then actually look at use, it would vary by the type of intellectual property. In trademarks, for instance, there are searches, and then your freedom to operate would vary enormously depending on the intellectual property zone.
The heat maps—as they were, about activity and collaborations—are an indication that can often give you a sense, because you know who the commercial actor is and then you can do the digging as to what the actual value is.