Attorney Lim Chang-kuk, during his approximately 16-year tenure as a public prosecutor, held various positions including Deputy Prosecutor of the Seoul Central District Prosecutors' Office, Chief of the Criminal Division 2 at Ansan District Prosecutors' Office, Chief of the Criminal Division 3 at Ulsan District Prosecutors' Office, and Senior Prosecutor of the Major Economic Crime Investigation Team at the Seoul Western District Prosecutors' Office. He investigated a wide range of cases, including corporate corruption cases such as illegal funds involving major conglomerates, corruption cases related to redevelopment projects and 'bribery and personnel misconduct' cases involving a local government head official. He also has experience in revising corporate-related legislation while dispatched to the United Nations Commission on International Trade Law (UNCITRAL).

Transitioning from the prosecution to practicing law, Attorney Lim has been involved in significant cases such as defending vice-chairmen of a major financial group in violations of the Capital Markets Act and personnel misconduct cases of a Minister of Korea. He also represented cases involving coin fraud by major corporations, defensed in program supply fraud cases accused by a major corporation, and teaches cybercriminal law at the Industrial Security Department of Chung-Ang University, demonstrating a blend of theoretical and practical expertise in IT and cybercrime.