Amazon.com Inc's shares fell as much as 4.2 percent on Friday after the company missed Wall Street targets for its closely watched cloud computing business. Shares fell to $804 in early trading, a day after the company reported lower-than-expected fourth-quarter revenue and said it would continue to spend heavily this year, as it looks to take control of its delivery chain and expand its video service around the world. At least six brokerages cut their price targets on the stock, bringing the median target price to $925.