The Legal Nature of the Climate Change Regime: Fluctuation between Lex Lata and Lex Ferenda

International law is faced with the challenge between lex lata and lex ferenda in nature. Lex lata , based on legal positivism, has binding obligations and a top-down compliance structure, while lex ferenda , on the contrary, is based on non-binding values and bottom-up adherence architecture. Determining the legal nature of each regime is important because depending on its nature, the assessment of its efficiency will be different. The question is whether the evolution process of the climate change regime is towards lex lata or lex ferenda ? Examining indicates that initially the Framework Convention, in terms of some indicators, was lex lata and in others it was lex ferenda . Subsequently, to address the shortcomings of the Convention, especially the lack of legally binding targets and timelines, the Kyoto Protocol shifted to a strong lex lata . Finally, due to the inefficiency of the Protocol arising from the institutional design failure, the Paris Agreement became a lex ferenda . Analyzing the Sharm el-Sheikh Implementation Plan (2022) indicates that the Regime is still mainly based on ideal values and non-binding commitments. For the future transformation of the Regime into an efficient lex lata , a gradual process, rather than a strong shift, shall be followed that is being done in the case of the fund for loss and damage that was previously lex ferenda and is becoming lex lata