If you find a stock that you believe is undervalued, it is important to try to determine the reason for the undervaluation. As Buffett wrote about poker in his 1987 letter to shareholders, “If you’ve been in the game 30 minutes and you don’t know who the patsy is, you’re the patsy.”
Interestingly, some value investors, such as David Einhorn of Greenlight Capital, invert this process. Rather than first looking for undervalued stocks based on quantitative screens, for example, low multiples of price to earnings or price to book value, they first identify areas of the market where undervaluation is likely to be present and then search for good companies within that undervalued sector.
When Buffett purchased shares of the Commonwealth Trust Co. of Union, New Jersey, he indentified the reason that was largely responsible for the depressed price of the company’s stock. It was because the company was not paying a cash dividend. Identifying this reason reduced the probability that there were other unknown or poorly understood reasons why the stock price was depressed which could have materially reduced the intrinsic value of the company and lead to a permanent loss of capital.
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