But the reason the Seattle company can still be classified as a growth stock is its cloud business, Amazon Web Services. And AWS had some problem areas that haven't garnered much attention yet.
Amazon earned $4.23 a share, missing the Wall Street consensus estimate of $4.62. Revenue rose 24% to just under $70 billion. That figure exceeded the estimate of $68.8 billion.
Amazon has been aggressively investing in one-day e-commerce delivery for its Prime members. Analysts had priced those investments into their valuations in September, and Amazon still missed earnings expectations.
The stock is trading off a bit more than 4.65% to $1,698 in the premarket Friday.
At Amazon Web Services revenue grew 35% year-over-year to $9 billion -- and missed estimates of $9.1 billion. Last year's Q3 revenue growth for the segment was 45%, and that 10-percentage-point drop has some analysts slightly concerned.
Adding to that concern, higher marketing and infrastructure costs related to the segment shrank its operating margin by 6 percentage points year-over-year.
AWS must perform.
It's the company's fastest growing business, and organizations increasingly are adopting cloud storage for data over traditional physically based storage methods.
AWS is also Amazon's highest margin business. It already accounts for more than 60% of Amazon's operating profit and that proportion isn't expected to decline any time soon.
On the earnings call Thursday evening, "We went 37 questions into the EPS call before someone finally asked about AWS...huh?!" wrote RBC Capital Markets analyst Mark Mahaney in a note. "Of all the AMZN pieces, the AWS growth and profit outlook probably deserves the most investor attention right now."
CFRA analysts cut their price target on Amazon to $1,950 from $2,200, partly due to lower AWS estimates.
Other analysts also cite Microsoft's (MSFT) - Get Report cloud business as a threat. "Competitive pressure from Microsoft needs to be monitored," Tom Forte, analyst at D.A. Davidson & Co. told TheStreet. Microsoft posted a solid quarter, reporting Azure (cloud) revenue growth of 50%.
Still, "The rest of the AMZN long thesis is fully intact," said Mahaney. "And we strongly doubt AWS is at a negative inflection point."