Skip to main content
Nancy Guillén Espinosa

Nancy Guillén focuses her practice on global energy, including oil and gas, administrative, and environmental law. She advises international companies dedicated to upstream activities, including public bidding procedures, drafting of contracts and designing legal strategies.



  • Legal advice to global energy companies in the prequalification phase for bidding process by Mexican authorities.°
  • Assistance to multinational oil companies to comply with contractual obligations and regulatory procedures established in the Mexican legal framework related to the energy sector.°
  • Drafting of contracts for exploration and extraction of hydrocarbons projects.°
  • Legal strategy planning for the implementation of contracts for exploration and extraction of hydrocarbons.°
  • Management of inter-institutional procedures related to the publication of tenders for the bidding of contractual areas.°
  • Migration procedures of Allocations to contracts for exploration and extraction of hydrocarbons.°
  • Legal opinions related to energy regulation, including assignment and change of control; administrative rescission; prior consultations, and migration procedures.°

°The above representations were handled by Ms. Guillén Espinosa prior to her  joining Greenberg Traurig, S.C.

  • Assistant Area Director, in the Ministry of Energy, Under-Ministry for Hydrocarbons, General Oil Contracts Department, 2015-2017
  • Consultant, Muvoil Consulting, S.C., 2017-2018


  • J.D., with honors, Universidad Nacional Autónoma de México, 2015
  • Mexico
  • Spanish
  • English