Аннотация:The article shows the possibilities of using non-smooth analysis and polynomial measures to study network effects, build optimal prices in mathematical models of multilateral markets and a fair distribution of benefits between participants. The presentation of mathematical constructions is preceded by a mean-ingful analysis of the problems that arise at the intersection of economics and law in connection with the costs of opportunistic behavior, the validity or non-justification of the application of antitrust regulation measures. With the use of modern mathematical tools, the idea of combining the properties of private and public goods inherent in telephone networks and almost all objects of urban infrastructure are being devel-oped. The article turns out to be large in volume, interdisciplinary and complex. Therefore, the presentation of the results is preceded by a rather large introduction. It can be considered as an independent article, which gives a brief overview of modern works on network effects and digital platforms, as well as some undeservedly forgotten works and events.