One of the verdant new fields the Dodd-Frank act has opened for litigators involves the Securities and Exchange Commission’s say-on-pay rule, which requires public companies to put executive compensation up for an advisory shareholder vote every two years. The rule went into effect in January. By May, Dena Aubin of Reuters was already reporting on a surge in shareholder derivative suits claiming boards breached their fiduciary duty by pushing through pay packages that shareholders voted down.