The General Dynamics settlement must be approved by the court and also by an independent fiduciary that represents the interests of the 401(k) participants, according to the statement.

A spokesman for General Dynamics refused to comment on the tentative settlement.

The suit against General Dynamics and Fiduciary Asset Management was one of more than a dozen that the St. Louis-based Schlichter law firm filed against large companies in 2006 and 2007. All the lawsuits alleged 401(k) participants were paying excessive fees for their retirement plans or had been misled about the costs of their plans.

Gregory Ash, a partner who specializes in employee benefits at Midwestern law firm Spencer Fane Britt & Browne, notes that three 401(k) fee cases have now been settled, and another case, Tibble v. Edison International, was decided last month in the plaintiffs' favor.

“Overall, plaintiffs' lawyers are starting to get some traction but it's still a very narrow, uphill road for them,” Ash says. “They are reaping some benefit for their efforts. But the courts have established some pretty significant hurdles for them to overcome to win on the merits. And there have also been a number of dismissals of other lawsuits that have favored defendants.”

Caterpillar, another of the companies sued by Schlichter, settled that lawsuit last November for $16.5 million. And in April, Beverly Enterprises, a Little Rock, Ark.-based nursing home operator, agreed to pay $6.5 million to settle a 401(k) fee suit brought by another law firm.

There have been court verdicts in two other 401(k) cases. Last month, a court found that California utility Edison International had improperly used retail shares of mutual funds, rather than cheaper institutional shares, for three of the options in its 401(k) investment line-up. In 2007, in Hecker v. Deere, Deere prevailed. That case was appealed all the way to the U.S. Supreme Court, which refused in January to review the decision.

For more about Caterpillar's settlement, read Caterpillar Settles 401(k) Fee Lawsuit.