When doing industry analysis using Porter's 5 Forces, we often have a choice between a broader and a narrower definition of the industry. In the broader industry definition, we would have more firms (of different types) included in the industry as rivals, whereas in the narrower industry definition we have fewer firms included as industry rivals with some types of firms excluded from the industry. Now, let's imagine you chose to use such a narrower industry definition for analyzing an industry rather than a broader one.

In your Porter's 5 Forces analysis using this narrower industry definition, what should you typically do with all the (types of) firms that you have excluded from the industry?