AbstractScholars of work disputes have mostly focused on alternative dispute resolution (ADR) by employer organizations. With the context of work changing, disputes in mediated “gig” work should also be subject to scholarly analysis. To examine factors influencing the impartiality of ADR by labor market intermediaries, we focus on intermediary dispute handlers and the relationships these private regulators have with dispute parties. Building on the ethnography of disputing literature, we uncover how, depending on the structure of their marketplaces, intermediaries may frame their third‐party role differently and influencing the impartiality of their ADR processes. The paper illustrates this point, drawing on fieldwork inside a labor platform and a temporary staffing agency. Existing explanations focus on the promise of impartiality of ADR by an external third‐party. Using interview, observational, and archival data, we analyze third‐party roles in mediated labor markets and posit that impartiality is primarily linked to marketplace structure.