Retirement plans operated by US employers collectively hold trillions of dollars in assets, so they have naturally become a target for litigation under their governing statute, the Employee Retirement Income Security Act, commonly known as ERISA. Under ERISA, plan fiduciaries are subject to duties of loyalty and prudence, which can be enforced by the US Department of Labor or by private civil actions. Class actions targeting ERISA plan fiduciaries have been on the rise. Financial institutions are potentially implicated for the plans that they provide to their own employees and for the services that they provide to their clients. Mayer Brown partners Nancy Ross and Brian Netter discuss recent trends in ERISA litigation.