In 2005, Yahoo invested $1 billion in Alibaba. 10 years later, its stake was worth more than $30 billion after the Chinese giant went public

In January 2015, Yahoo planned to hand shareholders its 15% stake in Alibaba tax-free. Nine months later, the U.S. Internal Revenue Service refused to guarantee that exemption. Proceeding without an official blessing meant risking a multi billion dollar tax bill for shareholders.…

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