While marijuana is already listed as a Schedule I controlled substance by the federal government, an anti-cannabis organization actually petitioned the Food and Drug Administration (FDA) to add the drug to another restricted list. But even the FDA said that was ridiculous.
The FDA rejected a petition to add marijuana to a list of restricted substances that are not "generally recognized as safe and effective." An organization called Drug Watch International submitted the petition as a way to put pressure on cannabis companies to not make claims about the medical benefits of marijuana. But the FDA said they already have authority to remove over-the-counter cannabis medications making unsubstantiated claims and therefore the move was not necessary.
The regulatory agency has actually made some moves against false advertising in the cannabis industry. Last November, the FDA sent out a series of warning letters to companies that made products containing CBD that advertised "tumor-shrinking" properties. They said they wouldn't allow these companies to prey upon people with cancer and give them false hope when there are other, more proven medications that can fight it.
Of course, this decision by the FDA doesn't really mean much for cannabis businesses other than they can be somewhat sure the FDA isn't going to needlessly go after them in the near future. Marijuana is still listed as a Schedule I controlled substance by the federal government, and that's the only classification that really matters.