What is non-kosher about sprint gum?

Sprint gum may contain some non- kosher ingredients like gelatin or food coloring (that comes from insects or pigs). But even if they don't, if they don't pay to be supervised by Rabbis that make sure the Jewish laws are being met, they don't get the mark that says that they are kosher, and Jews cannot know if they are or not. Lastly, even if the gum does not contain any non- kosher ingredients, it can be made in a factory that also makes non- kosher things, and so it might have in it by accident those ingredients.