According to reports, a lawsuit was filed in California on January 10, accusing the Interpublic Group of Companies of undertaking "various accounting manipulations to overstate revenues", and that junior members of staff were forced to "cook the books".
The suit goes on to say: "The net result of these account manipulations was that in certain years during the period 1997 through 2001, operating profit was overstated by as much as 500%."
Interpublic is already facing a formal investigation over $181.3m (拢114m) in overstated revenues, mainly stemming from revenue being double-booked at offices in the McCann-Erickson Europe network.
The new lawsuit has been filed on behalf of investors who purchased Interpublic stock between October 28 1997 and October 16 2002. It names individuals including John Dooner, chairman and CEO; Sean Orr, chief financial officer; and the former chairman and CEO Philip Geier.
The filing quotes an unnamed former finance executive at McCann-Erickson's Colombian office, who says that there was increasing pressure from Interpublic bosses to meet budgets, "even if that required overstating reported revenues and understating reported expenses".
Earlier this week, the US financial watchdog said that, having been informally investigating the financial irregularities at Interpublic, it was now going to formally look into dealing at the advertising agency group.
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