Most-favored-nation (MFN) clauses in wholesale contracts have been the subject of recent controversy and renewed antitrust scrutiny. We demonstrate that a vertical environment where MFN clauses may be endogenously adopted shares equivalence properties with an environment where a final goods monopolist sells a good exhibiting negative consumption externalities directly to consumers and is faced with an exogenously imposed uniform pricing requirement. By leveraging these equivalence results, we are able to offer a new and useful framework for assessing the welfare effects of wholesale MFNs and which generates new insights.