This study summarizes the issues in the promotion of data distribution, how huge digital platformers conduct in the market, and the actual regulations and initiatives for them. In particular, it briefly examines the actual status of litigation under US antitrust law and the issues. The study discusses the following five points: First, it highlights the delineation of the relevant market, which is also the first entry point in competition analysis. Second, it undertakes the existence of monopoly power, which requires the analysis of dominant firms. Third, it analyzes the conduct of forming, maintaining, and strengthening market power. Fourth, it analyzes the consumer damages. Fifth, it discusses whether antitrust actions are needed to solve the problems and remedies.