Saidin is a Professor of Law at the Faculty of Law, Universitas Sumatera Utara (USU). He previously served as Vice Dean III of the Faculty of Law from 2014 to 2016, followed by Vice Dean I from 2016 to 2021. He also served as Head of the Master's Program in Law at the Faculty of Law, USU, for the 2021–2026 term, as well as Chair of the Academic Affairs, Planning, and Budget Commission of the Academic Senate for the 2019–2024 term. He currently serves as Chair of the Trademark Appeal Commission, having been elected unanimously for the 2024–2027 term. His areas of expertise include Intellectual Property Law (IP Law) and Civil Law.