Trust deficits in sunset industries: Legitimacy Deficits as antecedents to cross-sector partnerships

The oil and gas (O&G) sector, a key sunset industry, faces rising decarbonisation pressures from regulation, markets, and scrutiny. However, unilateral corporate attempts to address these pressures often struggle to secure social acceptance, creating legitimacy deficits that threaten the industry's social license to operate. Grounded in Legitimacy, Institutional, and Stakeholder theories, this study examines the micro-foundations of these deficits using a qualitative big-data approach, drawing on data from Reddit and YouTube between 2020 and 2024. Our thematic analysis revealed five legitimacy deficits that serve as antecedents for specific cross-sector partnerships: 1) Knowledge and Deception; 2) Greenwashing and Carbon Credit Cynicism; 3) Industry Transition Realities and Investments; 4) Technical Solutions and Alternative Approaches; and 5) Consumer Responsibility and Societal Change . These trust deficits help explain why firm-led claims may lose credibility and why firms in sunset industries may seek externally validated cross-sector partnerships as one route to rebuilding credibility. Through integrated theoretical perspectives, the study contributes conceptual insights into how specific legitimacy deficits can increase the salience of verification, governance, technical, and normative partnerships. It also identifies Cross-Sector Language and Framing as a moderating variable, showing how clear, shared communication protocols may shape whether partnerships are perceived as credible routes to legitimacy restoration.