as age discrimination. As such, it expressed an opinion that the management of the wage peak system be improved through rationally adjusting the wage reduction ratio and implementing appropriate target measures so as to meet the purpose of the system.561) B) Issues of the Wage Peak System After the Supreme Court Decision It is expected that many similar lawsuits will be filed in the wake of this Supreme Court ruling. However, according to the standard set by the Supreme Court, not all wage peak systems to maintain the retirement age are invalid, and whether or not the wage peak systems implemented by other companies will be recognized as valid may vary depending on the justification and necessity of the purpose of introducing the system, and the extent or period of actual wage reduction. In fact, there are cases where the wage peak system was held valid in a lawsuit related to the wage peak system to maintain the retirement age after the Supreme Court ruling.562) In Korea, the wage peak system was first introduced by the Korea Credit Guarantee Fund in 2003, and has expanded to around public enterprises. After the enforcement of the Elderly Employment Act in 2013, which set the retirement age to 60 or older, it was expanded to private enterprises. As of June 2021, 52% of businesses with more than 300 employees operate a wage peak system. The wage peak system is mainly used for the maintaining the retirement age or extending the retirement age. If it was introduced against the background of the mandatory retirement age of 60, it generally belongs to the retirement age extension type. Since the Supreme Court decision is on maintaining the retirement age, it is difficult to apply it directly to the extension of the retirement age system implemented by most companies. In the case of the wage peak system for extending the retirement age after the Supreme Court decision, the Supreme Court standard was sometimes cited as a reference, and there was also a case where it was not appropriate to use it as it is.563) However, even in 561) NHRCK, Decided on Nov. 8, 2022, 22JinJeong0328100, Decided on Dec. 22, 2022, 22JinJeong0812300 562) Seoul Eastern District Court, Decided on Oct. 27, 2022, 2020GaHap113172 563) Seoul Central District Court, Decided on Jun. 16, 2022, 2019GaHap592028; Daejeon High Court, Decided on Dec. 7, (Cheongju)2022Na50254 227