This study extends the literature on price efficiency by empirically investigating the speed with which cross-firm information, derived from technologically connected peer firms, is incorporated into the stock prices of focal firms. Drawing on patent-based technological linkages among Chinese listed companies, we develop two novel cross-sectional price efficiency metrics: an information diffusion delay measure and a return synchronicity index. Our findings reveal that corporate digital transformation, a critical strategic initiative for organizational renewal, exerts both direct and spillover effects on cross-firm price efficiency. These effects operate through three distinct channels: (1) network spillover effect acting on the information supply, intermediary, and demand sides; (2) improved governance transparency; (3) enhanced market liquidity. Notably, the impact of digital transformation on cross-firm information efficiency is particularly pronounced for growth and mature firms, technology- and capital-intensive firms, as well as those with higher governance quality and lower operational efficiency.