Perhaps the most obvious candidate for a lump of coal is the social networking company whose IPO was bungled so badly. True, the immediate fault can be traced to the deal’s underwriters and to the exchange that was ill-prepared for the frenzied attempts on the part of investors to transact trades, but the company played a role, too. Had it not acceded to an IPO price that clearly was very richly priced, with no room for error, a stumble wouldn’t have had such a negative impact on the share price and the news of a disappointing initial earnings release wouldn’t have been as devastating. Even after a strong bounce in recent weeks, the stock remains 26 percent below the IPO price.