Purpose: The purpose of this research was to investigate the spread pattern of Korean legal certification systems and their impact on industry performance. Methods: It first analyzes the life cycle of legal certification systems and classifies them into four categories based on the spread patterns in a chronological view. A survey study is then conducted to find out the impact of legal certification systems on financial performance. Both the legal mandatory certification systems and the legal voluntary certification systems are included in the survey. Results: Four spread patterns of legal certification systems are sustainable growth, stagnation after growth, decrease after growth, and repetition of growth and declination. 56% of 293 certified corporations responded positively about the financial impact of their certification systems. Conclusion: The policy makers can utilize the results of this study in designing additional certification systems as well as promoting the current legal certification systems.