Abstract
Industry-wide multi-stakeholder partnerships (MSPs) are increasingly mobilized to address sustainability scrutiny, yet research remains largely firm-centric and tells us little about how legitimacy dynamics shape the partnership itself over time. Building on legitimacy-as-process, we study the Sustainable Apparel Coalition (SAC) and its rebranding as Cascale, tracing how legitimacy is sought, conferred, challenged, and repaired from 2011–2024. Using 730 archival documents, we combine qualitative content analysis with a an AI-assisted coding workflow (“Legitimacy Explorer”) that identifies legitimacy behaviours (seeking vs. conferring) and mechanisms (identity, associative, organizational) across time. Temporal bracketing shows four phases: Rise (2011–2014), Institutionalization (2015–2019), Crisis (2020–2022), and Repair (2023–2024). We show that early legitimacy rests on associative ties to prominent founders, later becomes embedded in tools and governance, then collapses under regulatory and greenwashing scrutiny around the Higg Index, prompting intensified legitimacy-seeking and a suspension of legitimacy-conferring. Repair involves identity reconstitution, stronger organizational mechanisms (verification, third-party review, policy alignment), and strategic reconfiguration of relationships (including selective distancing by members). We contribute a process model of recursive legitimacy in MSPs, demonstrate reciprocal legitimacy exchange between coalitions and members, and illustrate how AI-supported text analysis can scale process research while retaining interpretive control.