Heavy Growth Puts Drag on Amazon's Bottom LineBig spending and lower-than-expected forecast for the holiday season put a cloud over the e-commerce giant's shares.

Amazon reported a disappointing third quarter on Thursday in the period leading up to holiday season. Investors responded by pummeling the stock in after-hours trading, driving it down 10% to $280 a share. Here are the key points from the earnings report.

What you need to know: Amazon traditionally funnels much of its profits into expanding its already gargantuan business, resulting in razor-thin margins — and this quarter proved no different. The e-commerce giant reported a $437 million loss on revenues of $20.58 billion, a 20% revenue increase year-over-year, but well below Wall Street's estimate of $20.84 billion.

A significant chunk of that money went into content and technology — a spending area that jumped 40%. That's unsurprising given Amazon's announcement last quarter that it would spend over $100 million on original video content, including the well-received original TV show, "Transparent" with "Arrested Development" actor Jeffrey Tambor.

The big numbers: $27.3 billion and $30.3 billion. That's the sales range Amazon expects for this holiday season, the company's busiest time of the year. That represents growth of between 7% and 18% versus last year, but again, less than what analysts forecast.

What you might have missed: Amazon had an extremely busy summer. It acquired Twitch, the video-game streaming site, for $1.1 billion, unveiled a credit card reader for the smartphone called Amazon Local Register and brought its same-day grocery delivery service, Amazon Prime Fresh, to New York. Amazon also launched the Fire phone, which is widely believed to be a dud. On Thursday's earnings call, CFO Tom Szutak suggested it was too early to call the Fire phone a failure given its launch just 90 days ago. Said Szutak: "When ever you launch something new, there's a wide range of outcomes, but it's also early."