We study how updates in pay floors set by collective bargaining agreements (CBAs) shape the wage structure in Italy. We estimate stacked event-panel difference-in-differences models around changes of contractual minima and trace distributional impacts. Pay-floor hikes of 2.2% on average raise mean log FTE daily wages by 2.2%, but effects are near zero at the 10th percentile and stronger at the 90th, implying inequality enhancing wage-rate responses. This asymmetry reflects both within-agreement heterogeneity, as lower-paid workers within CBAs respond less, and between-agreement heterogeneity, as low-wage CBAs exhibit weaker pass-through. Non-compliance with pay floors is higher in low-wage CBAs, thus it is a potential driver of asymmetries even if its level is not affected by wage updates. Pay-floor hikes reduce employment and days worked only among low-wage workers and only among full-time jobs, which may further
contribute to the muted wage response in the lower tail through selection mechanisms.