(a)
Circumstances giving rise to liability
In addition to any liability which he may have under any other provisions of this part, a fiduciary with respect to a plan shall be liable for a breach of fiduciary responsibility of another fiduciary with respect to the same plan in the following circumstances:
(1)
if he participates knowingly in, or knowingly undertakes to conceal, an act or omission of such other fiduciary, knowing such act or omission is a breach;
(2)
if, by his failure to comply with section
1104
(a)(1) of this title in the administration of his specific responsibilities which give rise to his status as a fiduciary, he has enabled such other fiduciary to commit a breach; or
(3)
if he has knowledge of a breach by such other fiduciary, unless he makes reasonable efforts under the circumstances to remedy the breach.