Attention to Rivalry among Online Platforms and Its Implications for Antitrust Analysis

Many online businesses, including most of the largest platforms, seek and provide attention. These online attention rivals provide products and features to obtain the attention of consumers and sell some of that attention, through other products and services, to merchants, developers and others who value it. The multi-sided business of seeking and providing attention is fluid with rivalries crossing boundaries defined by the features of the products and services. It is also dynamic. Rivals introduce new products and services, some involving drastic innovation, frequently. Online attention rivals impose competitive constraints on each other. Product differentiation tempers the significance of these constraints in particular situations. But the relevant differentiation mainly involves aspects of the attention that is procured and sold rather than, necessarily, particular features of the products and services used for acquiring and delivering that attention. Antitrust analysis should consider these competitive constraints in evaluating market definition, market power, and the potential for anticompetitive effects. Most importantly, antitrust analysis should focus on competition for seeking and providing attention rather than the particular products and services used for securing and delivering this attention. The existence of competition among attention rival