That’s an incredible stretch of the definition. The other parties are other parties besides the buyer and seller. > Moreover, even if you want to limit extern

That’s an incredible stretch of the definition. The other parties are other parties besides the buyer and seller. > Moreover, even if you want to limit externalities to being completely third-party... sure: Pollution. More electrical generation capacity needed. ^this is an externality, everything else is just a poor understanding of the concept.