Hemp Industries Association v. DEA, Nos. 03-71366, 03-71693 (2004)
"We have previously held that the definition of ?THC? in Schedule I refers only to synthetic THC, and that any THC occurring naturally within Cannabis is banned only if it falls within the Schedule I definition of ?marijuana.?...We reiterate that ruling here: in accordance with Schedule I, the DEA's relevant rules and regulations may be enforced only insofar as they ban the presence of marijuana or synthetic THC."

That case was regarding Hemp Seeds, that may have Trace Amounts of THC. And the quote above is a quote about the interpretation of the Law. And because THC on Marijuana Seeds does not Constitute "Marijuana", we can conclude that an extract with maybe 75% Natural THC and 25% Terpenes or other things, would not be "Marijuana".

The safest way to stay in line with that ruling though, would be to use THCa Distillate since that is the current Purest form of THC.

United States v. Forbes, 806 F. Supp. 232 (D. Colo. 1992)
Olsen V DEA 878 F.2d 1458, 279 D.C. 1, 58 USLW 2023
Normaco v. DEA, 375 F.3d 1148 (D.C. Cir. 2004)
Linder v. United States 268 U.S. 5 (1925)
Gonzales v. Raich, 545 U.S. 1 (2005)
Gonzales v. O Centro, 546 U.S. 418 (2006)
Washington v. Sessions, et al 1:17-cv-05625
Church of the Lukumi Babalu Aye, Inc. v. Hialeah,508 U.S. 520 (1993)
Masterpiece Cakeshop, Ltd. v. Colorado Civil Rights Commission, 584 U.S. ___ (2018
Burwell v. Hobby Lobby, 573 U.S. ___ (2014)