33 USC 2710 - Indemnification agreements

(a) Agreements not prohibited 
Nothing in this Act prohibits any agreement to insure, hold harmless, or indemnify a party to such agreement for any liability under this Act.
(b) Liability not transferred 
No indemnification, hold harmless, or similar agreement or conveyance shall be effective to transfer liability imposed under this Act from a responsible party or from any person who may be liable for an incident under this Act to any other person.
(c) Relationship to other causes of action 
Nothing in this Act, including the provisions of subsection (b) of this section, bars a cause of action that a responsible party subject to liability under this Act, or a guarantor, has or would have, by reason of subrogation or otherwise, against any person.