Post‑Chevron Reality for Cannabis and Hemp: How Loper Bright and Corner Post Reshape FDA and DEA Rule Challenges in 2025–2026

Introduction

The U.S. Supreme Court’s 2024 decisions in Loper Bright Enterprises v. Raimondo and Corner Post, Inc. v. Board of Governors dramatically upended the regulatory landscape for cannabis and hemp stakeholders in 2025 and beyond. By overturning the forty-year-old Chevron deference doctrine and broadening who can bring Administrative Procedure Act (APA) challenges, the Court has exposed the FDA and DEA to stricter judicial scrutiny—particularly in areas of statutory ambiguity that have long defined the rules for products like hemp-derived CBD, cannabinoids, and synthetic derivatives. In an era already shaped by federal rescheduling debates and a new Farm Bill on the horizon, these rulings make the next two years a high-stakes period for regulated cannabis and hemp business owners, compliance officers, investors, and policymakers.

Chevron Is Dead: What Did Loper Bright Change?

The Supreme Court’s decision in Loper Bright did away with the principle that courts must defer to agencies’ reasonable interpretations of ambiguous statutes. Now, when the FDA or DEA interprets a vague provision of the Food, Drug, and Cosmetic Act or the Controlled Substances Act (CSA), courts apply independent judgment:

• No more automatic deference — Judges will not simply side with FDA/DEA on unclear statutes.
• Heightened scrutiny of agency reasoning — Agency rules and guidance must be well-grounded in the statutory text and administrative record.
• New window for litigation risk — More challenges to ambiguous or controversial regulatory stances are likely—and may be more successful.

For the cannabis and hemp sector, where Congress has repeatedly left gray areas (e.g., the legal status of different cannabinoids, “synthetic” vs. “naturally derived” compounds, or the status of CBD in food and supplements), this marks a watershed moment.

What Does Corner Post Change? Challenging "Old" Rules, Statute of Limitations

In Corner Post, the Court ruled that the six-year APA statute of limitations to challenge a regulation begins to run not when the rule is issued, but when a specific plaintiff is first injured by that rule (read Supreme Court opinion). This means:

• Operators entering the market in 2025-2026 can challenge FDA/DEA rules that were finalized years or even decades ago, as long as their "injury" is recent.
• Wave of new litigation — Businesses excluded or harmed by legacy rules on hemp, cannabis, CBD, or synthetic cannabinoids now have standing for fresh legal challenges.

This dramatically increases both agency exposure and business opportunity to reshape the rules.

FDA Guidance & Rulemaking Vulnerabilities: Where Are the Weak Spots?

1. Hemp-Derived CBD in Foods and Supplements

The FDA has asserted that CBD cannot be sold as a dietary supplement or added to foods, citing its prior investigation as a drug (Epidiolex). Yet, clear statutory text is lacking; Congress never unambiguously prohibited hemp-derived cannabinoids in supplements or food after the 2018 Farm Bill.

• Key compliance takeaway: Courts can now examine the FDA’s rationale without deference, and the evidentiary record behind the agency’s risk-based limits will come under intense scrutiny. Businesses may petition or litigate for narrowly tailored, evidence-based regulations, rather than outright bans.
• FDA’s refusal to engage in rulemaking on CBD and minor cannabinoids, relying on non-binding guidance letters, is particularly vulnerable (CannabisRegulations.ai analysis).

2. Delta-8, Delta-10, and Minor Cannabinoids

FDA ambiguity around intoxicating hemp-derived cannabinoids (e.g., Delta-8 THC) in foods, beverages, and supplements remains hotly contested. With Loper Bright, new players can challenge restrictive or inconsistent FDA guidance, especially in the absence of formal rulemaking.

3. "Synthetic" Issues

Courts may now weigh how the FDA interprets “synthetic” cannabinoids—particularly when that term is undefined in federal law—and whether the application of old rules to novel technologies (e.g., biosynthetics, isomerization) is justified.

DEA Rulemaking and Interpretations: What’s at Stake?

The DEA’s interpretation of the 2018 Farm Bill has been a flashpoint for conflict, often drawing bright lines between “hemp” (legal) and “marijuana” (controlled), but the agency has offered little statutory clarity:

1. THCa and "Total THC" Standards

DEA has asserted through guidance letters and informal pronouncements that non-decarboxylated THCa (the acidic precursor to THC) should count toward total THC for controlled status. However, the underlying statutes reference only delta-9 THC concentration. Under Loper Bright, courts are less likely to defer to DEA’s interpretation unless it’s tightly anchored to the statute’s text and a robust administrative record (Canna Law Blog, Foley Hoag).

2. Delta-8, Delta-10, and Other Hemp-Derived Cannabinoids

Federal circuit courts have recently rejected DEA’s attempts to control hemp-derived cannabinoids that meet Farm Bill definitions, underscoring that post-Chevron, courts are making their own calls on statutory interpretation—even where agencies argue for broad authority.

3. Synthetic Cannabinoids and Analogues

The distinction between “naturally derived” and “synthetic” cannabinoids—central to classifying substances as controlled under the CSA—has been handled by DEA via guidance, not clear regulations. With Loper Bright and Corner Post, affected businesses can mount fresh, text-based challenges to these interpretations.

Evidentiary Burden on Agencies: What Must FDA and DEA Now Prove?

In a post-Chevron world, both FDA and DEA will face a steeper burden when defending rules and guidance:

• Detailed administrative records — Agencies must show in-court that their interpretations flow clearly from statutory text and are justified by the record.
• Transparent risk evaluations — FDA’s health claims (e.g., about CBD safety) and DEA’s risk assessments must be explicit, well-reasoned, and open to challenge.
• Less reliance on informal guidance — “Dear Colleague” letters, policy statements, and FAQs are now on shakier legal footing than formal, notice-and-comment rulemaking.

Compliance Timelines, Litigation, and Operator Strategy (2025–2026)

Businesses expanding into cannabis, hemp, and minor cannabinoid products should:

1. Monitor Agency Record-Building and Comment Opportunities

With upcoming rule proposals for CBD, synthetic cannabinoids, and rescheduling, operators should swiftly:

• Submit comments to build a favorable record
• Marshaling scientific evidence supporting reasonable, industry-friendly interpretations

2. File or Join Strategic Litigation

Thanks to Corner Post, even newly-formed businesses can contest old rules if those rules now harm them. Strategic challenges—particularly where agencies rely on ambiguous language—are more likely to garner favorable judicial review over blanket prohibitions or vague, broad rules.

3. Day-to-Day Operational Compliance

• Stay current on state-level requirements, which may diverge from shifting federal guidance
• Document compliance efforts to demonstrate good-faith adherence

4. Adapt Internal Policies

• Reevaluate compliance and risk policies in light of the new era of legal uncertainty and litigation risk
• Prepare for potential regulatory changes over 2025–2026 as the FDA, DEA, and Congress adjust to the post-Chevron world

Looking Ahead: Farm Bill, Rescheduling, and Rulemaking Horizon

2025–2026 is the most dynamic period cannabis and hemp have seen in decades, due to:

• Ongoing rescheduling petitions and rulemaking at DEA (potential movement of cannabis from Schedule I)
• Congressional action on the next Farm Bill, expected to address intoxicating hemp and novel cannabinoids
• Agency initiatives for science-based CBD, supplement, and food rules

Post-Chevron, industry advocacy and well-supported challenges will play a crucial—perhaps decisive—role in the evolution of federal cannabis regulations.

Key Takeaways for Cannabis and Hemp Businesses

• Loper Bright eliminates deference; courts will scrutinize FDA/DEA interpretations much more rigorously
• Corner Post empowers recent market entrants to challenge decades-old agency rules that now cause harm
• Vulnerable areas: FDA’s CBD food/supplement ban; DEA’s total THC, synthetic, and minor cannabinoid interpretations
• Operators must: Engage in commenting and litigation, maintain rigorous compliance documentation, and closely monitor federal rulemaking

Stay ahead of rapidly shifting federal cannabis and hemp policy. For the latest regulatory updates, strategic compliance insights, and tailored support, visit CannabisRegulations.ai.