Shocks to Product Networks and Post-Earnings Announcement Drift

This paper examines whether shocks to less visible product market network peers explain industry level post-earnings announcement drift (IPEAD). On the real-side, we find that peer earnings shocks propagate slowly through the peer network, creating a complex and conditional autocorrelation structure in earnings shocks. This impacts the financial-side, and IPEAD arises only when shocked peers are less visible in the network and when shocks are driven by persistent supply-side shocks to expenses rather than by demand-side shocks to sales. In addition, IPEAD is particularly strong when 10-K expense disclosures are opaque. Collectively, our results suggest that inattention to less visible peers, complex autocorrelation in earnings shocks, and a poor informational environment on the expense side are likely channels that generate IPEAD. IPEAD returns are economically large in subsamples motivated by this explanation