Our Team

Meet the Team

Brian Tannenbaum | Nick Trost | Robert Burk | Lisa PittmanElena Collins

Brian Tannenbaum


(720) 420 – 1270

Brian Tannenbaum manages T|T|B’s transactional and regulatory practice. A Colorado native, Brian received both his undergraduate and law degrees from the University of Colorado at Boulder, where he graduated summa cum laude. After finishing law school in 2008, Brian spent approximately a year and a half in Buenos Aires, Argentina, where he worked as a research assistant for the Universidad de Palermo, School of Law, and also taught classes at the Universidad Abierta Interamericana.
Upon returning to Denver in 2010, Brian founded Tannenbaum, Trost and Burk, LLC. Brian has extensive experience with a variety of practice areas including business formation and restructuring, mergers and acquisitions, asset sales, real estate and land use matters, regulatory compliance and licensing, tax matters and estate planning.

Since 2012, Brian has spent much of his time working with clients involved in Colorado’s cannabis industry. He has become an industry expert in Colorado marijuana laws and the legal issues which many marijuana businesses face in navigating the complex and confusing regulatory environment in which they must operate. He understands the interplay between the laws regulating marijuana business investment, land use requirements, state and local licensing rules, and compliance with state marijuana regulations. Brian has the skill set to tackle whatever matter your marijuana business may face.


University of Colorado School of Law, J.D., 2008

University of Colorado, B.A. Geography, summa cum laude, 2005.

Honors and Memberships:

  • Board Member, Roots and Branches Foundation, Rose Community Foundation
  • Phi Beta Kappa

Nick Trost


(720) 420 – 1244

Nick Trost has developed a diverse civil litigation practice in multiple areas, including commercial disputes, personal injury, medical malpractice, insurance “bad-faith,” and products liability. He has appeared in Courts across Colorado, in the U.S. District Court for the District of Colorado, the Colorado Court of Appeals, and the Colorado Supreme Court. Nick also has extensive experience in alternative dispute resolution (“ADR”), having participated in multiple mediations and arbitrations. With a background in science, Nick particularly enjoys tackling cases with complex technical issues.

Before starting his own practice in April, 2014, Nick worked for two law firms, practicing first with an insurance-defense litigation firm, before moving across the aisle to represent Plaintiffs in personal injury and insurance disputes. In addition to litigation, Nick has assisted multiple clients with real estate and corporate transactions, estate planning, probate administration, and various criminal matters.

During law school, Nick clerked for a firm specializing in the litigation of complex water, environmental, and land use issues in Colorado and also interned with the National Wildlife Federation in Boulder, Colorado. In 2006, he received a special certification in International Environmental Law from the University of Costa Rica in San Jose, Costa Rica. Nick was also awarded a distinguished summer clerkship with Justice Michael Bender, former Chief Justice of the Colorado Supreme Court.


University of Colorado School of Law, J.D., 2008

University of North Carolina at Chapel Hill, B.A. Political Science; B.A. Geological Sciences, 2005.

Robert Burk


(720) 420 – 1282

Robert (Rob) Burk has extensive commercial and criminal litigation experience. Born and raised in Denver, Rob went to Regis Jesuit High School before attending Yale University and the University of Colorado School of Law.

After graduating from law school, Rob began serving his country as a lieutenant in the United States Navy Judge Advocate General’s Corps. First stationed in Lemoore, California, he served as a defense attorney, trying over a dozen cases to verdict and participating in over 100 judicial hearings and proceedings. He also headed the base legal assistance and tax preparation programs, helping over 1000 clients with a wide range of matters.

Rob was then stationed in Washington, D.C., and was selected as a law clerk for the Navy-Marine Corps Court of Criminal Appeals. In this capacity he assisted with the analysis and drafting of criminal appeals decisions. While in Washington, Rob also served as an appellate defense counsel, representing clients before the Navy-Marine Corps Court of Criminal Appeals. Upon completion of his active duty Navy service, Rob returned to Colorado to clerk for Judge Marcia Krieger, the Chief Judge of the U.S. District Court for the District of Colorado. As a law clerk, Rob gained extensive experience in both criminal and civil litigation assisting in the management of Judge Krieger’s civil and criminal docket.

After his clerkship with Judge Krieger, Rob worked at one of the preeminent boutique litigation firms in the country, Wheeler Trigg O’Donnell, LLP. As a civil litigator at Wheeler, Rob was exposed to all phases of civil litigation, from complaint to trial, and has personally drafted dozens of pleadings, discovery documents, evidentiary motions, dispositive motions, jury instructions and many other types of documents. Rob represented both plaintiffs and defendants in a variety of industries, including the insurance, oil and gas, mining, automobile, healthcare, pharmaceutical, service and hospitality, and education industries.

At TTB, Rob focuses his practice on civil litigation and corporate counselling.  His clients include corporations and individual business people, whether plaintiffs or defendants.  He has won numerous cases at the pleadings stage, arbitration, and trial.  He takes pride in his thorough and powerful writing, including pleadings, discovery, motions and briefs, and actively cultivates his thoughtful, composed, skillful, and persuasive courtroom presence.  Rob’s successes include numerous victories in bet-the-company litigation in a variety of areas, including disputes involving trade secrets, employees, ownership/investors, demands for accounting, commercial landlord-tenant issues, and myriad other contract-based disputes.

Rob also provides in-house counsel assistance for several large and growing corporations, overseeing daily legal needs such as regulatory compliance, contract review and drafting, deal negotiation and closing, employee policy and dispute resolution, financing, lease and development issues, and litigation.

He recognizes that his clients, whether large or small, want favorable resolution of their disputes and challenges in an efficient and cost-effective manner.  Rob’s goal is to always keep this in mind, while still providing thorough and expert legal advice and services.


University of Colorado School of Law, J.D., 2008;

Yale University, B.A., 2005.

Elena Collins

Business Consultant

(720) 204 – 2586

Elena Collins has developed comprehensive skills in helping clients establish and grow their marijuana business through proper licensing and regulatory compliance. Born and raised in Vermont, Elena completed her bachelor’s degree at the University of Vermont with a focus on small business development, economics, and marketing. Elena applied her passion for business development and entrepreneurship into her work at T|T|B in expanding the consulting department and offering clients personal hands-on assistance to achieve their business goals.

Elena joined T|T|B in early 2016, and her success and dedication to learning the ins-and-outs of the cannabis industry and keeping current with the regulatory changes within the marijuana industry has made her a valuable asset to the T|T|B team.


University of Vermont, B.A., 2015.

Lisa Pittman

Special Counsel


Throughout Lisa’s 18 year career, she has litigated and tried disputes relating to labor & employment, breach of contract, commercial banking, fraud, fiduciary duty, construction defect and injury, deceptive trade practices, premises liability, professional liability, property, and products liability. Lisa also possesses extensive expertise in complex commercial insurance coverage matters, having both defended insurance companies and advocated for policy holders in commercial and residential property matters.

As she began to focus her practice on the legal cannabis and hemp industries, for 2½ years, Lisa worked under a former DEA Task Force Commander and Narcotics Prosecutor to learn the federal government’s stance on cannabis legalization and enforcement to counsel clients on federal risk mitigation and local law enforcement issues. Lisa began to represent a broad range of clients from investors to ancillary service and product providers to “plant touching” companies. Some of these clients have now expanded into other countries. In pursuit of becoming a leader and authority in this area, Lisa has become familiar with the many challenges facing cannabis and hemp businesses, such as tax, banking, insurance, and regulatory compliance issues, and she has grown a vast network of experts to assist in these areas. This work brought her from Texas to Colorado, and eventually led her to serve as Special Counsel to Tannenbaum, Trost & Burk, LLC.

Knowing the “end game” from her previous litigation work, Lisa has become adept at negotiation and contract drafting, and her a broad base of knowledge in many legal areas provides her the ability to give all around business advice to clients in the cannabis and hemp industries, such as with investment and growth strategies, as well as risk management and mitigation to avoid civil litigation, criminal prosecution, or regulatory violations. Lisa has assisted cannabis and hemp license applicants in multiple states across the country, including guiding Louisiana State University through its rollout of Louisiana’s medical marijuana program. A native Texan, Lisa has been working in the legalization movement in Texas and throughout the South, earning the title, “The First Lady of Texas Cannabis Law.”

Lisa is a leader in the American Bar Association (ABA), a nationwide membership network of elite attorneys. She presented its first cannabis Continuing Legal Education (CLE) course at its annual meeting in New York City in August 2017. She is Vice-Chair of the Business Litigation, Product Liability, and Corporate Counsel Committees of the Tort, Trial, and Insurance Law Section (TIPS). She is a founding Steering Committee member in the newly formed Cannabis Law & Policy Task Force Committee, as a result of the success of her groundbreaking CLE. Lisa also writes annual articles tracking the evolution of contract law across the country for the TIPS Law Journal. She graduated from the American Bar Association’s Leadership Academy in 2015 and the Austin Bar Association’s Leadership Academy in 2016. She graduated from Leadership Austin, Essentials Class of 2017. Lisa is frequently asked to speak and write articles for organizations around the country.


University of Texas at Austin, 1997, B.A., English, Minor Psychology and Spanish

University of Houston Law Center, 2001, J.D.

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