Yahoo’s $8 Billion Black Hole: How Did Valuation Happen?

Bloomberg Businessweek: If you go by one popular analysis of Yahoo’s valuation, the Internet company is worth approximately -$8 billion. The minus sign isn’t a typo. Given another three years — the amount of time Marissa Mayer recently suggested she would need to complete a turnaround — it’s possible her high-risk strategy could bear fruit. But it seems unlikely she will be able to hang on anywhere near that long.