Wisconsin Republicans File Bill to Ban Hemp-Derived THC Products

While current law exempts hemp from the definition of tetrahydrocannabinol (THC) if it contains no more than 0.3% delta-9 THC on a dry weight basis, AB 503 broadens and tightens the framework by including all forms of THC—such as tetrahydrocannabinolic acid—in that 0.3% limit. Proponents of the bill say this closes a “loophole” in the 2018 federal farm bill that legalized hemp. The proposal has been sent to the Committee on State Affairs for initial consideration.

The bill also establishes clearer definitions for “industrial hemp” and “hemp-derived cannabinoid products.” Industrial hemp would cover plants grown for stalk, grain, seed, oil, or research purposes. Hemp-derived cannabinoid products would mean items containing cannabinoids for human or animal use, such as through ingestion or inhalation, but would specifically exclude any synthetic cannabinoids or compounds that are not naturally produced by the plant. Products marketed as having effects similar to THC would also fall outside the new hemp definition.

Importantly, AB 503 excludes viable cannabis seeds with THC levels above the 0.3% threshold, as well as any artificially manufactured cannabinoids, from being classified as hemp. It also gives the Department of Agriculture, Trade and Consumer Protection continued oversight for testing and certification. Crops exceeding 0.7% above the legal limit would be subject to seizure and destruction.

With its referral to the Committee on State Affairs, lawmakers will now weigh whether to advance the measure to the full Assembly. If enacted, the proposal would significantly reshape Wisconsin’s hemp market, particularly for producers and retailers dealing in hemp-derived cannabinoid products.