Interpublic, the world's third largest advertising group, has also been rapped for the delay in releasing its fourth quarter earnings due to accounting difficulties over acquisitions made between 1996 and 2001.
US-headquartered advertising agency group Interpublic must be wondering what it has recently done to displease the gods.
Celebrations last week for its scoop of microchip maker Intel's $300 million (€223m, £156m) global ad account have been overshadowed by a review of its $2.8 billion General Motors media buying business.
The car making giant has announced GM Mediaworks in Michigan and at LCI in New York, where the huge account currently resides, will have to do battle with Starcom MediaVest, a unit of rival group Publicis.
Last year Starcom won GM's $30 million outdoor account from Mediaworks.
According to a GM spokeswoman the review is being undertaken because: "The competitive landscape has changed so much that it's time to take a fresh look at things."
The company says the most significant problem it has identified involves $145m in revenue and $25m of net income "that may have been improperly recognised".
Data sourced from AdAge.com; additional content by WARC staff