Nathan Cassell focuses his practice on patent prosecution and counseling in the Chemical & Life Sciences industry area. Mr. Cassell is a registered patent attorney and has experience in preparing patent applications and opinion letters, as well as advising clients on intellectual property matters. His experience includes all areas of patent portfolio evaluations, related opinion work, and due diligence reviews of companies working in the biotechnology and medical device areas. Mr. Cassell also provides scientific and prosecution advice in dispute matters, including infringement analysis.

Mr. Cassell represents a wide variety of U.S. and international clients, ranging from individual inventors, start-ups, small businesses and pre-public companies, to large academic institutions, multinational corporations and Fortune 500 companies.

Mr. Cassell is a certified mediator.

Professional & Community Activities

American Bar Association, Member

American Intellectual Property Law Association, Member

Colorado Bar Association, Intellectual Property Section, Member

Jefferson County Mediation Services, Volunteer


  • University of Denver College of Law, J.D. (1994)
  • Northwestern University, B.S., Biomedical Engineering (1988)

Bar Admissions

  • Colorado (1995)


  • U.S. Patent and Trademark Office (1998)

Who We Are

What fully engaged means to me:

Fully engaged means identifying and implementing a legal strategy, based on a sound understanding of technology and the law, to effectively safeguard our clients' intellectual property assets.

Suite 600, 1400 Wewatta Street
Denver, CO, 80202
t +1 303.607.3299
f +1 303.736.4260