As businesses rebound from the international economic slump, mergers and acquisitions have multiplied. More than 21,000 deals totaling $1.9 trillion in volume were announced globally between January 2010 and November 2010, marking a 12 percent volume increase from 2009 igures, according to Bloomberg’s 2011 M&A Outlook. Market experts predict continued increases in M&A activity this year, particularly in the energy industry.

The uptick in transactions is rife with opportunity for some savvy plaintiffs firms that have latched onto a lucrative litigation tactic: suing companies for deals that are allegedly unfair to shareholders, either in disclosure or pricing. The lawsuits, sometimes filed within hours of a deal’s announcement, are profitable for plaintiffs firms because companies often settle in order to move forward with their transactions.