Using a sample of Korean listed firms from 2011 to 2022, this study investigates how firm misvaluation affects green patenting activity. The results show a positive relationship between misvaluation and subsequent green patenting, and this relationship is driven ex- clusively by overvalued firms. The relationship remains robust across alternative model specifications and estimation techniques, including Tobit, Poisson, system GMM, and propensity score matching. Mechanism tests indicate that this pattern is not explained by increased access to external capital. Instead, it is more pronounced when firms are likely to be more sensitive to market environmental preferences. Taken together, these findings suggest that green patenting activity may primarily be driven by valuation-based incentives to cater to perceived market expectations, rather than to signal firm fundamentals. This insight highlights the need for investors and policymakers to carefully distinguish between green patenting that reflects genuine environmental commitment and that which is undertaken primarily to influence market perceptions.