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LONDON, Dec 19 (Reuters) - WPP, the world's largestadvertising agency, said on Monday that three of itssubsidiaries had received subpoenas from the U.S. Department ofJustice as part of an investigation into video productionpractices in the industry.
Run by the high-profile British businessman Martin Sorrell,WPP said that both the group and its subsidiaries were fullycooperating with the enquiries.
Rival groups Interpublic Group of Cos, Omnicom Group and Publicis Group SA had already announcedthat they were subpoenaed as part of the investigation.
The DoJ's antitrust division has been investigating whetherad agencies had rigged bids to favour in-house production units.
(Reporting by Kate Holton; Editing by Adrian Croft)
