Costly Signals and Cheap Talk: Measuring the Decoupling of ESG Routinisation and Greenwashing Risk

Greenwashing is a systemic challenge to sustainable finance, yet prevailing ESG metrics still tend to equate more disclosure with more sustainability. We develop a dual‐index framework to compare firms' ESG ‘talk’ and ‘walk’ using hard data. An ESG Routinisation Index approximates the costly integration of sustainability into emissions, safety and circularity routines, while a Greenwashing Risk Index measures environmental talk–walk misalignment by comparing environmental‐facing ESG assessments with peer‐relative environmental process improvement. Using a 5‐year panel of 593 large‐cap firms, we find that ERI is weakly related to ESG ratings but is associated with environmental innovation and short‐term margin compression, consistent with routinisation as a costly signal, whereas GRI is tightly aligned with ESG scores and tends to be rewarded by markets. Mapping firms into an ESG Talk–Walk Matrix reveals that ‘storytellers’—low routinisation, high talk–walk gaps—form both the largest group and a common transition destination over time.