The large-scale investor ESG paradox and greenwashing penalty: Evidence from Japanese GX transition bonds

As global markets shift beyond standard green bonds, transition finance has emerged to fund the decarbonization of hard-to-abate sectors. This study investigates the factors influencing the yield premium demanded by investors within Japan’s GX Climate Transition framework, the world’s first sovereign transition bond. Employing interval regression and robust Oster bounding ( δ = − 7.76 ), we decompose the stated yield demand into fundamental market frictions and three core ESG pricing dynamics. First, we find that standard illiquidity concerns are associated with a baseline risk premium of up to 5.7 basis points. Second, we identify a walk-the-talk discount, where investors with revealed ESG preferences accept a 3.4-basis-point yield reduction. Third, we uncover a large-scale investor ESG paradox: while small-scale retail investors display pricing neutrality, large-scale investors with heightened risk sensitivity demand a yield premium of 9.4 basis points. Fourth, our estimates indicate that this large-scale premium is consistent with a greenwashing penalty. Investors state a demand for compensation associated with the forward-looking ambiguity of transition labels, corresponding to an increase in stated required yields of over 15 basis points. The study results imply that the transition greenium is highly segmented by asset-size heterogeneity, providing empirical insights for policymakers and corporate issuers designing transition finance mechanisms.