When the Alibaba prospectus finally landed Tuesday night, Yahoo investors saw a lot they already knew. But there was a small detail that could soon send Yahoo shares higher.
Yahoo's valuation has long been supported by its 24 percent stake in the e-commerce giant, which is expected to begin trading in the U.S. later this summer. Through Yahoo's own disclosure, investors learned that Alibaba was generating revenue growth above 60 percent with a hefty $4 billion of operating profit in 2013.
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One figure that hadn't been disclosed: free cash flow. On page 15 of Alibaba's prospectus, the company discloses free cash flow over recent periods. Using those, it's possible to calculate 2013 full-year free cash flow of about $5.2 billion—larger than some investors expected. Free cash flow is a measurement of profitability that is often preferred by investors because it reflects how much cash the company has created that could be used for dividends, buybacks, or investments.