碳揭露、碳排放與股票流動性

本文透過2013年到2023年台灣上市上櫃公司在永續報告書內揭露的碳排放資料，探討公司的碳揭露、碳排放與自願揭露對股票流動性的影響。實證結果顯示，有揭露碳排放資訊的公司相比於沒有揭露的公司，資訊更加透明，有助於降低投資者和公司之間的資訊不對稱程度，並因此擁有更高的股票流動性。而自願揭露碳資訊的公司，相比受到法規約束強制揭露的公司，也擁有更高的股票流動性。當公司的碳排放量和碳密度越低時，代表其未來的碳風險越低，更容易受到投資者的青睞，因此擁有更高的股票流動性。此外，在以不同的方式衡量碳密度或控制樣本選擇偏誤下，結果仍維持穩健。最後，在樣本分群分析中，對於高汙染產業的公司，碳排放量對股票流動性的影響會比碳密度更顯著。機構投資者持股比例高的公司，碳排放對股票流動性的影響也比較小。

關鍵字

碳揭露；碳排放；碳密度；股票流動性

並列摘要

This thesis explores the impact of companies' carbon disclosure, carbon emissions and voluntary disclosure on stock liquidity through the carbon emissions data disclosed in the sustainability reports of Taiwan listed companies from 2013 to 2023. Empirical results show that companies that disclose carbon emissions information are more transparent than those do not, which helps reduce the degree of information asymmetry between investors and companies, and therefore has higher stock liquidity. Companies that voluntarily disclose carbon information also have higher stock liquidity than those forced to disclose by regulations. When a company's carbon emissions and carbon intensity are lower, it represents a lower future carbon risk, and it is more likely to be favored by investors and therefore has higher stock liquidity. The results remain robust either by alternative carbon intensity, or controlling for sample selection bias. Finally, subsample analyses show that the impact of carbon emissions on stock liquidity will be more pronounced for firms in high-pollution industries and firms with low institutional ownerships.