Sebastián has been an associate at Arrubla Devis since 2018 and previously served as director of the Corporate Law area of the firm Lloreda Camacho & Co., and as a lawyer for the Vice Presidency of Legal Affairs at ANDI. In the latter, he represented Colombian businessmen in several of the technical subcommittees of the Commission for the Coordination of Salary and Labor Policies and was a member of the Board of Directors of the Public Employment Service and the National Council on Labor Risks.

He has experience in advising national and foreign companies on contractual, corporate and foreign exchange matters, business reorganization processes such as mergers and spin-offs, company liquidation and all litigation matters related to these matters. He has been an undergraduate professor at EAFIT University and at the Universidad Pontificia Bolivariana, and of the Private Law and Commercial Law specializations at the latter.