Downer EDI has sought to blame KPMG for failing to detect accounting irregularities, the disclosure of which wiped some $500 million from the contractor’s valuation, forcing the professional services firm to resign as the company’s auditor.

Downer told investors on Monday that it would bring a claim against auditor KPMG in the Victorian Supreme Court as part of a class-action lawsuit launched against the company by aggrieved shareholders after the 2022 disclosure that it would have to restate profits by tens of millions of dollars due to misreporting of revenues and work-in-progress.