Sean T. McAllister

Founding Attorney


Elected to the Board of Directors of the National Cannabis Industry Association 2017-2019

Sean T. McAllister is one of the nation’s leading cannabis business attorneys, licensed to practice law in both Colorado and California. Sean’s legal work focuses on the complex interplay between corporate law and state cannabis regulatory structures and federal law. Sean is an experienced attorney who helps his clients make important decisions when launching and operating their businesses, including:

  • Choosing the correct corporate form (C Corp, LLC, S Corp, partnership, etc.),
  • Helping clients bring in investment money while complying with state and federal securities laws,
  • Structuring deals with lenders to bring in capital and pay it out while complying with state regulatory rules,
  • Structuring corporate governance documents to ensure all of the owners understand how the business will operate,
  • Helping clients understand the complex tax rules that effect the cannabis industry, including IRS Code 280E,
  • Helping clients understand state’s cannabis regulatory regime,
  • Helping clients understand the risks and other issues that arise under federal law (ex. FDA regulation, DOJ priorities),
  • Defending companies or individuals in state administrative proceedings when there is an alleged rules violation,
  • Helping clients buy and sell their businesses
  • Helping clients plan exit strategies, and
  • Assisting clients in understanding their intellectual property and how to protect it.

In addition, Sean is an experienced litigator, having tried approximately 40 cases to a judge or jury. Sean has represented numerous business owners in civil litigation revolving around ownership disputes, breach of contract, employment law disputes, and other disputes. Sean defended and successfully resolved the nation’s first product liability lawsuit against a cannabis manufacturer. In addition, Sean has sued regulators over enforcement actions, litigated pesticide standards for cannabis grows at the state and local level, and negotiated settlements for some of the most serious cannabis rules violations. He has litigated local bans on cannabis dispensaries and sued several cities and counties for the implementation of the cannabis laws.

Sean is a recognized leader in the cannabis industry. In 2004, he founded Sensible Colorado, which worked on all of the ballot initiatives in Colorado that culminated in recreational cannabis legalization in 2012. Given his leadership skills, Sean has received the following awards or leadership positions:

  • 2004-2012 Chairman of the Board of Directors, Sensible Colorado
  • 2009 Friend of Reform Award, Sensible Colorado
  • 2012-2014 Spokesperson for Colorado NORML
  • 2013 MVP, Cannabis Business Awards
  • 2015 MVP, Cannabis Business Awards
  • 2016-2019 5280 Magazine, Top Marijuana Lawyer
  • 2018 MG Magazine, 30 Powerful Litigators You Should Know In Cannabis
  • 2017-2019 Elected to the Board of Directors of the National Cannabis Industry Association
  • From 2000 to 2003, Sean served as an Assistant Attorney General with the State of Colorado where he focused on regulatory compliance and administrative law.

Representative Matters

  1. Defended the nation’s first products liability case against a infused product manufacturer with a successful outcome.
  2. Defended Colorado’s only federal criminal prosecution of a dispensary owner for federal money laundering/Bank Secrecy Act violations with a successful outcome. Sean acted as the state law regulatory expert in the case, along with criminal defense co-counsel.
  3. Helped a prominent cannabis brand expand their operations into over 10 states/countries through licensing agreements, joint ventures, and new companies.
  4. Overturned a denial of a cannabis license by the City of Boulder in an appeal to a County Judge by convincing the Judge that the company was entitled to an extension of time to complete permitting over the City’s objections.
  5. Represented a cannabis security company in civil litigation when sued by a customer to a store who claimed the security company should have protected him from robbery after leaving the store. The Court returned a directed verdict in our client’s favor. The ruling ended the case in the client’s favor without requiring us to go to a jury verdict.
  6. Represented dispensary owners in a civil litigation case where growers claimed to be owed money or promised ownership in exchange for their cultivation services. The verdict came back 100% in favor of the dispensary owner.
  7. Represented a cannabis cultivation licensee in summary suspension case where the entire business was shut down on suspicion of connections to the black market and was able to get the company re-opened. No company had every been summarily suspended by the cannabis regulator in Colorado and then re-opened.
  8. Defended a pesticide recall case where state and local regulators agreed to release holds on millions of dollars worth of cannabis wrongfully designated as contaminated.
  9. Closed dozens of M&A/sale documents amounting to many tens of millions of dollars in deals to buy/sell cannabis businesses.
  10. Helped a dispensary negotiate and close on a celebrity licensing agreements with two major cannabis celebrities that passed scrutiny of the state regulator.
  11. Sued a Colorado town for shutting down a dispensary after previously permitting it, then drafted a ballot initiative that was later approved by local voters to allow re-opening of the dispensary.
  12. Sued the Colorado Marijuana Enforcement Division regarding due process violations in the implementation of the rules, which led to a positive resolution of the dispute for the client.