Bank of America's legal woes? No worries for investors

Lately it seems that barely a day passes without a new legal headache arising for Bank of America (BAC). Monday was no different, as a group of pension funds filed a class-action suit in a federal court in Manhattan seeking "billions of dollars" in damages stemming from bonuses paid to Merrill Lynch executives around the time of the companies' merger late last year.

The suit comes after a federal judge tossed out a settlement between Bank of America and the SEC over similar issues and brings the two sides closer to a trial next year. And it's just one of several high-profile investigations into the Merrill takeover, including a congressional inquest and a probe by the New York attorney general, among others. Yet Bank of America's stock has remained resilient, outperforming the S&P 500 on the year and climbing 435 percent since falling to $3.14 in early March. Shouldn't investors be more worried?