29 U.S.C. § 1110
Exculpatory provisions; insurance
(a)
Except as provided in sections 1105(b)(1) and 1105(d) of this title, any provision in an agreement or instrument which purports to relieve a fiduciary from responsibility or liability for any responsibility, obligation, or duty under this part shall be void as against public policy.
(b)
Nothing in this subpart shall preclude—
(1)
a plan from purchasing insurance for its fiduciaries or for itself to cover liability or losses occurring by reason of the act or omission of a fiduciary, if such insurance permits recourse by the insurer against the fiduciary in the case of a breach of a fiduciary obligation by such fiduciary;
(2)
a fiduciary from purchasing insurance to cover liability under this part from and for his own account; or
(3)
an employer or an employee organization from purchasing insurance to cover potential liability of one or more persons who serve in a fiduciary capacity with regard to an employee benefit plan.
( Pub. L. 93–406, title I, § 410 , Sept. 2, 1974 , 88 Stat. 886 .)