(October 29, 2018, 2:23 PM EDT) -- BOSTON — A 401(k) plan trustee on Oct. 24 filed a motion to stay an Oct. 15 mandate issued by the First Circuit U.S. Court of Appeals to allow the trustee to seek review from the U.S. Supreme Court on the issue of who bears the burden of proof on loss causation in an Employee Retirement Income Security Act dispute between the 401(k) plan participants and the plan trustee (John Brotherston, et al. v. Putnam Investments LLC, et al., No. 17-1711, 1st Cir.)....