Any brands protected by American law must be independently-owned, with full transfer of all branding, patents, trade secrets, intellectual assets and physical assets.

So, for example, for even a single bottle of Perrier to be sold in America, it needs to have been made by a company registered with the brand name of Perrier, with exclusive use of that name within the country, independently owned and under zero control by Nestle, being manufactured using the exact same process with the exact same ingredients, and having control of the exact same patents and American-side infrastructure.

America is such a large marketplace that it would be impossible to split a company like this. Patents alone would prevent this, forcing Nestle to divest themselves of each individual subsidiary.