UPDATE: The Supreme Court issued its unanimous opinion in Tibble on Monday, May 18. The Court ruled in favor of the 401(k) participants and held that ERISA’s fiduciary duty requires a continuing duty, “separate and apart from the duty to exercise prudence in selecting investments at the outset,” to monitor plan investments. Significantly, participants will be able to bring a claim of breach of the continuing duty of prudence so long as the alleged breach occurred within six years of the suit. Employers, therefore, must undertake consistent quarterly or annual reviews of investments, and must systematically consider the prudence of each investment at that time. Read the Court’s opinion here.