Motivated by the prevalence of trade-size clustering in financial markets, this study examines whether this trading irregularity affects intraday price dynamics. Based on a global sample, we document that stronger trade-size clustering is associated with lower temporary price impact, consistent with the stealth trading hypothesis. Meanwhile, a positive interaction between clustering and permanent price changes further confirms that clustering trades convey information, suggesting that they originate from informed investors. After partitioning sizes into top, round, and non-round groups, we find that all are informative, despite the finding that top and round (non-round) sizes have more (less) clustering.