Purpose: Business model innovation is an important way for small and medium-sized platform enterprises (SMPEs) to gain competitive advantage in the digital economy. Based on social capital theory and dynamic capability theory, this study examines the role of alliance management capabilities (AMC) in platform business model innovation (PBMI) in SMPEs and will explore the moderating effects of technological turbulence (TT) and institutional pressure (IP). Design/methodology/approach: To validate the research objectives, questionnaires were distributed to 500 randomly selected SMPEs, yielding 286 valid responses. Structural equation modeling (SEM) and fuzzy-set qualitative comparative analysis (fsQCA) were used to analyze the data. Specifically, fsQCA was employed to identify the configurational paths leading to PBMI. Findings: The results indicates that inter-organizational coordination (IC), alliance portfolio coordination (APC), inter-organizational learning (IL), alliance proactiveness (AP) and alliance transformation (AT) had a positive effect on PBMI. TT and IP negatively moderated the relationship between AMC and PBMI. The fsQCA results, integrating specific dimensions of AMC implementation with TT and IP, revealed four configurational paths driving PBMI: “Adaptive coordination”, “Dynamic coordination”, “Learning coordination” and “Multiple coordination”. Practical implications: This study provides valuable insights to help SMPEs achieve PBMI. To this end, SMPEs should strengthen their AMC, manage the challenges posed by TT and IP and adopt a business model innovation strategy suited to their specific context. Originality/value: This study contributes to the literature on AMC, PBMI, TT and IP. Moreover, by combining SEM and fsQCA, this study uncovers the multiple configurational pathways through which SMPEs can enhance PBMI. The results provide guidance for facilitating SMPEs in achieving PBMI and advancing the field of platform business models.

In the volatility, uncertainty, complexity, and ambiguity (VUCA) era, platform enterprises face the critical challenge of balancing flexibility and controllability to sustain competitive advantage. Existing studies have examined these two dimensions separately but offer limited insight into their synergistic mechanisms within complex adaptive ecosystems. Drawing on the structural, cognitive, and relational dimensions of social capital theory, with a particular emphasis on institutional-level collaborative social capital among platform enterprises and their supply-chain partners, this study employs dynamic fuzzy-set Qualitative Comparative Analysis (fsQCA) to identify the configurational pathways through which Chinese platform enterprises achieve high sustainable development performance. Using panel data from Chinese A-share listed platform enterprises (2014–2024), we identify three equifinal configurational pathways sufficient for high sustainable development performance: (1) a cognitive-relational alliance-driven path, (2) a structural-relational hybrid synergy path, (3) a structural-cognitive flexible innovation path. Innovation value consensus emerges as a core condition across all pathways. These configurations are sufficient for platforms to exhibit flexible market responsiveness and strategic controllability under varying environmental conditions. The study advances social capital theory by demonstrating the multidimensional, synergistic, and context-sensitive nature of flexibility-controllability coupling in platform governance. It also provides managers with actionable insights for tailoring social capital investments to specific regional and strategic contexts.