Besides that, taxes are only a problem when you sell. If you look at the Yahoo Japan and Alibaba investments in terms of lookthrough earnings with all earnings held by the companies, the tax hit doesn't matter in the short term.
However, there is a tax maneuver being considered, called a "cash rich split off" [0]. Yahoo would do a tax-free swap of its Alibaba shares for a 5-year historic business owned by Alibaba. This historic business can have as much as two-thirds of its assets consisting of cash. Warren Buffett did something similar with his shares in GHC.
One question is why did Yahoo not pursue a cash-rich split off in its 2012 transaction with Ali? I would argue that it's most likely for political reasons. As unfair as it may be, the optics of Jerry Yang and Jack Ma teaming up to deprive the US Treasury of tax revenue is very different from the optics of Warren Buffett and Don Graham doing the exact same thing. I think they might still pursue it, just because that's a lot of money to leave on the table.
[0]: http://taxdidactic.blogspot.com/2011/10/yahoo-evaluating-cas...