In the spring of 2012, investigations revealed that Kellogg was using GMOs (Genetically Modified Organisms) in some of the 'natural' products they sell under the brand name of Kashi.*
Since the FDA does not regulate the word 'natural' in the way it does the word 'organic', Kellogg's claim of Kashi being 'natural' is not illegal.
And a "Yes" vote on Prop 37 would make this more than unethical, it would make it illegal.