["Journal of Product Innovation Management, EarlyView. ", "\nABSTRACT\n\nAcademic Summary\nProduct introduction events are frequent across industries, countries, and other contexts and part of the innovation strategy of many companies. However, the future performance of new products is uncertain, posing significant risks for firms and investors and leading to heterogeneous stock market responses. Identifying the generalized average effect of product introductions on firm performance and the drivers that may lower or enhance this stock market response remains imperative. This meta‐analysis synthesizes 1089 effects across 71 studies, quantifying the cumulative abnormal returns of the stock market in response to product introduction events. On average, product introduction events result in positive cumulative abnormal returns (CAR = 0.70%) but show substantial heterogeneity. However, the effect is strongly influenced by the type of event (i.e., externally‐generated announcements with a 2.60%‐points higher CAR than firm‐generated announcements) and a firm's industry (i.e., CARs are 1.90 [1.90, 1.67, 2.08] %‐points lower for durables [financial services, hospitality, pharmaceuticals] compared to consumer packaged goods). Further, temporal CAR patterns indicate that anticipatory effects (e.g., from information leakage) dominate the stock market response, with higher abnormal returns arising before (vs. after) the event. However, this temporal effect pattern reverses for externally‐generated announcements, indicating weaker anticipatory effects and a stronger information shock at the event. Finally, compared to physical goods, CARs for services are higher in countries with a higher percentage of services of gross domestic product.\n\n\nManagerial Summary\nProduct introduction events happen frequently across industries, countries, and other contexts. This research shows through a quantitative assessment of 71 studies that product introduction events create value for firms, generating an average positive stock market response of about 0.70%. But the stock market response to product introduction events varies considerably across event types, event timing, industries, and countries. The strongest driver of investor response is the source of the announcement. Product introductions communicated by independent third parties, such as regulatory agencies, generate substantially higher market reactions than firm‐generated announcements. The analysis further shows that markets often react before official announcements, likely due to information leakage and anticipation. Product introductions in consumer packaged goods tend to generate stronger stock market responses than those in other sectors. Finally, the market of the stock market matters: while a higher share of services of the GDP is generally associated with lower CARs, this effect is alleviated for new service introductions. Managers should therefore pay close attention to when, where and through whom they are communicating product introductions.\n\n"]