Marissa Mayer, CEO of Yahoo. (credit: Google+)

One of Yahoo’s best decisions was investing in a large chunk of Chinese e-commerce company Alibaba before it went public last year. Alibaba broke records with its initial public offering, and now Yahoo’s 15 percent stake in the company is worth $ 31 billion, according to the New York Times.

For the past year, CEO Marissa Mayer and Yahoo’s Board of Directors have been working to make that chunk of their business more valuable for investors, originally planning to spin-off the Alibaba shares into a separate holding company. But according to Nasdaq, in September the US Internal Revenue Service “declined to grant advance approval for the tax-free spin-off” of Alibaba.

This morning, Yahoo’s Board of Directors announced that it would reverse course, instead spinning Yahoo’s core businesses off and leaving the original Yahoo as a holding company for Alibaba shares. Yahoo’s assets and liabilities would form a separate public company, “the stock of which would be distributed pro rata to Yahoo shareholders,” Yahoo wrote in its press release.