493. Voidness of provisions protecting auditors from liability

(1) This section applies to any provision—
(a) for exempting an auditor of a company (to any extent) from any liability that would otherwise attach to him in connection with any negligence, default, breach of duty or breach of trust in relation to the company occurring in the course of the audit of accounts, or
(b) by which a company directly or indirectly provides an indemnity (to any extent) for an auditor of the company, or of an associated company, against any liability attaching to him in connection with any negligence, default, breach of duty or breach of trust in relation to the company of which he is auditor occurring in the course of the audit of accounts.
(2) Any such provision is void, except as permitted by—
(a) section 494 (indemnity for costs of successfully defending proceedings), or
(b) sections 495 to 497 (liability limitation agreements).
(3) This section applies to any provision, whether contained in a company's articles or in any contract with the company or otherwise.
(4) For the purposes of this section companies are associated if one is a subsidiary of the other or both are subsidiaries of the same body corporate.