U.S. District Judge Robert Pratt signed an order Tuesday approving an out-of-court settlement of a nearly 4-year-old lawsuit that challenged fees charged by subsidiaries of Principal Financial Group Inc. to manage mutual funds. As with many details of the case, terms of the settlement remain secret. The lawsuit was filed in October 2009 by an investor from California and another from Rhode Island who claimed the fees charged to manage bundled mutual funds were excessive and that the funds ultimately were overseen by directors who were more beholden to Principal than to investors. Principal maintained the fees were fair and in some cases were less than fees charged by competitors. Click here for a recent column by the Business Record columnist Dave Elbert about the case.