21 C.F.R. § 1308.35 : Food and Drugs — DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE — SCHEDULES OF CONTROLLED SUBSTANCES —EXEMPT CANNABIS PLANT MATERIAL, AND PRODUCTS MADE THEREFROM, THAT CONTAIN TETRAHYDROCANNABINOLS — Exemption of certain cannabis plant material, and products made therefrom, that contain tetrahydrocannabinols

(a) Any processed plant material or animal feed mixture containing any amount of tetrahydrocannabinols (THC) that is both:
(1) Made from any portion of a plant of the genus Cannabis excluded from the definition of marijuana under the Act [i.e., the mature stalks of such plant, fiber produced from such stalks, oil or cake made from the seeds of such plant, any other compound, manufacture, salt, derivative, mixture, or preparation of such mature stalks (except the resin extracted therefrom), fiber, oil, or cake, or the sterilized seed of such plant which is incapable of germination] and
(2) Not used, or intended for use, for human consumption, has been exempted by the Administrator from the application of the Act and this chapter.
(b) As used in this section, the following terms shall have the meanings specified:
(1) The term processed plant material means cannabis plant material that has been subject to industrial processes, or mixed with other ingredients, such that it cannot readily be converted into any form that can be used for human consumption.
(2) The term animal feed mixture means sterilized cannabis seeds mixed with other ingredients (not derived from the cannabis plant) in a formulation that is designed, marketed, and distributed for animal consumption (and not for human consumption).
(3) The term used for human consumption means either:
(i) Ingested orally or
(ii) Applied by any means such that THC enters the human body.
(4) The term intended for use for human consumption means any of the following:
(i) Designed by the manufacturer for human consumption;
(ii) Marketed for human consumption; or
(iii) Distributed, exported, or imported, with the intent that it be used for human consumption.
(c) In any proceeding arising under the Act or this chapter, the burden of going forward with the evidence that a material, compound, mixture, or preparation containing THC is exempt from control pursuant to this section shall be upon the person claiming such exemption, as set forth in section 515(a)(1) of the Act ( 21 U.S.C. 885(a)(1) ). In order to meet this burden with respect to a product or plant material that has not been expressly exempted from control by the Administrator pursuant to §1308.23, the person claiming the exemption must present rigorous scientific evidence, including well-documented scientific studies by experts trained and qualified to evaluate the effects of drugs on humans.

21 C.F.R. §1308.35

66 FR 51544, 10/9/2001