Business groups have asked the Supreme Court to rule that company retirement plans can continue investing in retail mutual funds.

The request was made Friday in a joint letter from the ERISA Industry Committee, the U.S. Chamber of Commerce, the Business Roundtable, the National Association of Manufacturers and the American Benefits Council.

The court will be ruling on case, Tibble vs. Edison International, that could give more power to 401(k) plan participants to sue over investments that charge excessive fees.

The business groups also asked the Supreme Court to uphold lower court cases that they say further ERISA’s goal of reducing regulatory burdens and litigation costs to encourage companies to offer retirement plans.

By siding with the suit and negating ERISA’s six-year statute of limitations on claims of fiduciary violations, the high court would be disrupting plan operations and participant interests by potentially requiring constant re-evaluations and changes to investment choices, ERISA Advisory Committee President and CEO Annett Guarisco said in a press release.

In Tibble, Edison International 401(k) plan participants claimed in 2007 that the company violated its fiduciary duty by including three retail-class shares of mutual funds as options when lower-fee institutional class shares were available eight years before the suit was filed.

The Department of Labor sided with the plan participants in its own letter to the high court, but the business group charged that letter constitutes a DOL attempt at “regulation via amicus brief.”

“By joining in petitioners’ broadside attack on retail-class mutual fund shares, the DOL is effectively saying that these are imprudent options for 401(k) plans, without having made any regulatory pronouncement to that effect,” said the group in its brief to the Supreme Court.