The Language of Greenwashing: SDG Omission and Opportunity‐Oriented Environmental Tone as Alert Metrics in Green Bond Disclosures

ABSTRACT Green bonds play a central role in sustainable finance, yet concerns about greenwashing raise questions about the credibility of issuers' sustainability disclosures. Using dictionary‐based methods and domain‐specific BERT transformer models, this paper proposes two greenwashing alert metrics and investigates their performance by analyzing sustainability reports of European corporate green bond issuers from 2019 to 2023. First, we develop the SDGs Omission Index (SDGOI), which measures the discrepancy between Sustainable Development Goals (SDGs) declared ex‐ante in green bond frameworks and those subsequently reported in sustainability disclosures. We show that the use of SDG‐specific language is associated with broader SDG coverage, whereas generic environmental language is not. Second, we introduce the Environmental Sentiment Metric (ESM), capturing opportunity‐oriented environmental sentiment. We find that a more opportunity‐oriented tone is positively related to SDG omission, ESG controversies, and greenwashing accusations. Together, SDGOI and ESM provide interpretable, disclosure‐based indicators that can support issuing greenwashing alerts in the European green bond market.