New Delhi, Sept. 21 -- Consumers rarely think about trust while placing an order online, scanning a QR code, or reading product reviews. They notice it only when something goes wrong: a counterfeit product arrives at their doorstep, a payment scam wipes out savings, or a fake review influences a purchase.

That invisible nature of trust sits at the heart of a growing challenge facing the digital economy. As generative AI lowers the cost of deception and enables creating convincing product images, seller profiles, and customer reviews, online marketplace are finding themselves in an escalating contest against increasingly sophisticated bad actors and organized fraud networks.

For Kebharu Smith, who leads Amazon's global Counterfeit Crimes...