A ConAgra spokesman said the shift of brands, including Marie Callender's, Reddi-wip, Hebrew National, Egg Beaters, Butterball and Armour and Eckrich packaged meats, is part of an overall company push to drive efficiencies and improve margins.
"This allows us to better leverage our scale among fewer agencies," he said.
ConAgra spent $29.5 million in measured media on the brands formerly handled by Grey, according to TNS Media Intelligence.
ConAgra declined to say where exactly the brands will be moved among its roster, which includes DDB and Leo Burnett as well as Interpublic Group of Cos.' Deutsch, New York, Fogarty Klein Monroe, Houston, and MDC Partners' Crispin Porter & Bogusky, Miami.
The shift does not include media-buying responsibilities that will continue to be handled by WPP's MediaCom. MediaCom and Grey Worldwide were formerly part of Grey Global Group, which WPP acquired earleir this year.