Troubled Interpublic, the world's third largest advertising group, has disclosed "possible employee misconduct" as part of ongoing investigations into long-standing accounting difficulties.

In a filing to the US Securities and Exchange Commission, the company has revealed "accounting errors attributable to such misconduct resulted from falsifying books and records; the violation of laws, regulations and company policies; the misappropriation of assets; and 'inappropriate' customer charges and dealings with vendors."

Despite the revelations IPG still hopes to meet its September 30 deadline and file accounts for the whole of 2004 and the first half of this year. Failure to do so could lead to de-listing on the New York Stock Exchange.

IPG, which has seen major clients pull their business in recent months including the giant Bank of America and parts of General Motors, says it will also have to re-state its earnings from 2000 to 2004.

Its accounting has been the subject of SEC investigations since 2002 when it re-stated five years of earnings after uncovering $68.5 million (€6m;£37.9m) charges in Europe that had not been properly expensed.

In a bid to calm the nerves of stockholders and clients, ceo Michael Roth says in a statement: "I have been clear since assuming my current responsibilities that our top priority is to fix our financial controls and leave accounting issues behind us. The comprehensive review of our financial results and processes that we have undertaken is consistent with this objective."

Data sourced from Adweek (USA); additional content by WARC staff