Motivated by the fact that investors have limited time and attention to process information, this paper provides a continuous-time equilibrium model to analyze the effects of a capacity constraint in the learning process of a representative investor, who optimally allocates her information capacity across multiple sources of uncertainty. Consequently, the cross-sectional structure of information and the resulting asset price dynamics are determined endogenously. The model provides implications on both consumption behavior and the cross-sectional differences in price informativeness in terms of supply of information, speed of price adjustments to fundamental shocks, and price reactions to firm disclosures.

We identify a new mechanism of opportunistic insider trading linked to attention-driven mispricing. Insiders are more likely to sell their company’s stock during periods of heightened retail attention and more inclined to buy when attention diminishes. The results are particularly pronounced for lottery-type stocks and firms with substantial retail ownership. We demonstrate that our findings—which relate to indicators of mispricing, retail order imbalances, and Robinhood herding episodes—extend to seasoned equity issuances and cannot be solely explained by firm fundamentals. Attention-based insider trading is less likely to result in SEC enforcement actions and persists across different regulatory regimes.

We document distinctly different clientele effects on investor attention and return responses to information. Macro news crowds out retail investor attention to firms’ earnings news by 49%. For stocks with high retail ownership, macro news dampens earnings announcement returns by 17% and substantially increases post-announcement drift, especially during high VIX periods. In contrast, macro news increases institutional investor attention to scheduled earnings announcements but not their attention to unscheduled analysts’ forecast revisions. The findings confirm the implications of rational inattention models and highlight the importance of considering clientele effects in understanding the effect of news on attention and asset prices.