August 11, 2005: Yahoo acquires 40 percent of Alibaba.com for $1 billion, and Alibaba takes over the operation of Yahoo China.
Yahoo Japan was also a joint venture between Yahoo and Softbank, with Yahoo holding about 50% of the ownership.
At some point, Yahoo stock was regularly trading at or below the estimated value of the overseas holdings. The part of the company that actually did stuff was valued at zero or less. In the acquisition, yahoo stockholders got cash for the operating business plus shares in holding company formed around the overseas holdings ... Over time, the holding company sold the holdings and distributed the proceeds to shareholders and ceased operating.
Yahoo made a $1b investment on Alibaba early on, and Alibaba was growing a lot, investors couldn't directly buy Alibaba, so they bought Yahoo hoping to eventually cash in.
Yahoo was valued at $44b at one time, and the $1b it put in Alibaba was valued at $40b. So 90% of Yahoo was the Alibaba investment. There was a whole spin off core business to separate it from the investment part drama, years and years of distraction and investors and board people who wanted their ~40x instead.
