For employers using Icon, the investment is a payroll deduct IRA. In this arrangement the employer is limited in their involvement with the plan, and therefore they are not subject to the rules governing 401(k)plans. Payroll deduct IRA's are not subject to ERISA, and there are no annual federal filing requirements or fiduciary responsibilities.
For more information on these regulations you can reference the IRS rules governing payroll deduct IRA's Here.