This seminar will examine the economic regulation of platform and network companies, with a particular focus on portions of the financial industry. We will start by studying economic regulation in the transportation, communications, and energy sectors. Tech platform companies will also be discussed. With these foundations in hand, we will turn to parts of the financial sector: money and payments, securities exchanges, derivatives clearinghouses, credit rating agencies, consumer credit bureaus, fintech companies, and other components of financial market infrastructure. How if at all should providers of these resources be regulated? We will explore common problems and unifying themes. Students will complete a research paper. Enrollment limited.