The news sparked a rally in Amazon stock, and sent shares of rivals like WalmartWMT, Instacart and DoorDashDASH sliding. The ...

The e-commerce giant is expanding significantly, but Instacart, DoorDash and Walmart have competitive strengths of their own.

Walmart’s adjusted earnings miss analysts’ estimates but second-quarter revenue tops forecasts. Tech stocks Palantir, Nvidia, and Intel extend losses.