ESG 起源於聯合國在 2004 年首次提出的「聯合國全球契約」，這反映了對
全球氣候變遷和社會發展議題的關注。ESG 是指環境（Environmental）、社會
（Social）和治理（Governance）三大指標的縮寫。旨在促進企業對環境、社會
和治理方面的責任和可持續發展。本研究探討了 2014 年~2022 年企業發布 ESG
永續報告書對企業價值的影響，永續發展相關議題在全球引起廣泛的關注。隨著
社會對永續發展的需求不斷增加，企業日益意識到了ESG因素對其業務和價值的
重要性。分析企業發布ESG永續報告書對企業價值的影響，不僅可以幫助企業更
好地理解其經營環境，也可以透過資訊揭露為投資者提供更全面的訊息，減少資
訊不對稱，促進永續發展的實現。

本研究以雙重差分模型（Differences-in-Differences model）結合動態面
板模型 (Dynamic panel-data model)，首先，透過雙重差分模型，以雙向固定
效應(Two-Way Fixed Effects, TWFE)迴歸，比較發布 ESG 永續報告書的企業（處
理組）與未發布ESG永續報告書的企業（對照組）的變化，來識別發布報告書的
因果影響。其次建立動態面板模型((Dynamic panel-data model)，採用廣義動
差法（Generalized Method of Moments）迴歸估計，進一步處理了模型中可能
存在的內生性問題，提高了估計的準確性和穩健性。主要被解釋變數為Tobin's
Q 用來代理衡量公司價值。

研究結果顯示，從2014年到2020年，企業發布ESG永續報告書對企業價值
的影響大部分不顯著，但在2021年開始，發布ESG永續報告書對企業價值產生
了顯著的負面影響，並在2022年達到最大。揭示了企業發布ESG永續報告書對
企業價值的影響是動態變化的，並且在最近的幾年表現出明顯的負面效果。

The concept of ESG originated from the United Nations' introduction of the "UN Global Compact" in 2004, reflecting concerns about global climate change and social development issues. ESG stands for Environmental, Social, and Governance,representing three indicators. It aims to promote corporate responsibility and sustainable development in these areas. This study investigates the impact of corporate ESG sustainability reports on firm value from 2014 to 2022. Sustainability-related issues have garnered widespread global attention. As society's demand for sustainable development continues to grow, companies are increasingly recognizing the importance of ESG factors on their business and value. Analyzing the impact of ESG sustainability reports on firm value not only helps companies better understand their operating environment but also provides investors with more comprehensive information through disclosure, reducing information asymmetry and promoting sustainable development.

This study employs a Differences-in-Differences (DID) model combined with a dynamic panel-data model. Firstly, the DID model, with Two-Way Fixed Effects (TWFE) regression, is used to compare changes between companies that publish ESG sustainability reports (treatment group) and those that do not (control group) to identify the causal impact of report publication. Secondly, a dynamic panel-data model is established, using the Generalized Method of Moments (GMM) regression estimation, to further address potential endogeneity issues in the model, enhancing the accuracy and robustness of the estimates. The primary explained variable is Tobin's Q, used as a proxy for measuring firm value.

The results indicate that from 2014 to 2020, the impact of publishing ESG sustainability reports on firm value was mostly insignificant. However, starting in 2021, publishing ESG sustainability reports had a significant negative impact on firm value, reaching its peak in 2022. This reveals that the impact of publishing ESG sustainability reports on firm value is dynamic and has shown a marked negative effect in recent years.

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