Summary Box: Amazon 3Q net income sinks

THE RESULTS: Inc. said Tuesday that its third-quarter net income sank 73 percent despite growth in sales as the online retailer continued to spend on expanding its operations. The company’s earnings missed analyst views and its fourth-quarter revenue outlook failed to impress investors.

WHAT IT MEANS: Amazon is building 17 sales fulfillment centers this year to make sure it can keep up as more consumers buy the products it sells. It’s also investing in its line of Kindle e-readers and the digital content it sells.

THE REACTION: Shares of Seattle-based Amazon fell 12 percent after-hours trading.