The suit, to be filed in a Massachusetts court, will also charge cereal giant Kellogg with marketing foods to children that are low on nutrients and high in sugar and health risks.
The plaintiffs want the court to block the companies from promoting the foods on platforms where children under the age of eight account for at least 15 percent of the audience, plus halt marketing via Web sites, toy giveaways, and other tactics.
The plaintiffs are the Center for Science in the Public Interest, Campaign for a Commercial-Free Childhood, and two Massachusetts parents.
The suit could charge Viacom $25 each time a Massachusetts child views an ad for the foods in question on its Nickelodeon network, and Kellogg each time a child views an ad for one of its products in question on Nick or another network. The plaintiffs said, however, that marketing changes are the goal--not monetary damages.
In multiple media reports, both Nickelodeon and Kellogg said they were committed to healthy lifestyles and responsible marketing practices.
Under Massachusetts law, parties must notify defendants 30 days before this type of lawsuit is filed, which they did yesterday.
Nickelodeon is the home of popular characters such as SpongeBob SquarePants, while Kellogg markets Apple Jacks and Pop-Tarts, among other brands.