New Delhi, Aug. 27 -- A supply chain report out of Taipei landed in Apple investor inboxes before markets opened Tuesday, and the stock spent the day repricing around it. Apple fell $2.13 to $234.67, a 0.9% decline, as analysts parsed reports that TSMC's 3nm process nodes for the iPhone 17 Pro's A19 Pro chip were producing lower than expected initial yields. The implication: Apple's highest-margin flagship could face constrained supply in the weeks immediately following its September launch.

it surfaces almost every year at roughly this point in the iPhone production cycle, because TSMC is always pushing process node limits to meet Apple's performance demands. What changes year to year is how much that constraint costs Apple in the first...