Maine's decision to impose unique burdens on ISPs' speech—while ignoring the online and offline businesses that have and use the very same information and for the same and similar purposes as ISPs—represents discrimination between similarly situated speakers that is impermissible under the First Amendment.
https://www.vice.com/en_us/article/qjdza5/big-telecom-say-it-has-first-amendment-right-to-sell-your-private-data