【摘要】 近年来,供应商—客户重叠现象在资本市场尤其是IPO市场中引发广泛关注,而学术界对该现象可能产生的经济后果尚未展开系统研究。文章以2007—2020年沪深A股上市公司为研究样本,考察了供应商—客户重叠关系对企业专业化分工的影响及其机制。研究发现,供应商—客户重叠显著提升了企业专业化分工程度,且企业与重叠交易方的权力差异越小,这种促进效应越显著,该结论在控制内生性问题后依然成立。供应商—客户重叠主要通过降低交易成本来推动企业专业化分工水平提升。这种促进效应在生产购销型企业、与供应商—客户地理距离较远的企业以及重叠关系持续时间较长的企业中表现更加突出,并能有效缓解供应链风险与外部环境不确定性带来的负面冲击。最后,供应商—客户重叠通过促进专业化分工显著提高了企业生产效率。文章的研究不仅为当前供应链安全背景下企业构建现代化分工体系提供了重要启示,也为市场监管者和投资者理性评估供应商—客户重叠的经济效应提供了理论依据。更多还原

【Abstract】 In recent years, the phenomenon where a supplier is simultaneously a customer of the focal firm(“supplier-customer duality”) has attracted considerable attention from the capital market, especially in the IPO market. However, little literature has investigated the motivations and consequences of supplier-customer duality.Taking A-share listed companies from 2007 to 2020 as the sample, this paper investigates the impact of supplier-customer duality on focal firms’ vertical specialization and its mechanisms. The results show that supplier-customer duality significantly promotes firms’ vertical specialization, and the smaller the power difference between firms and the counterpart, the stronger the positive effect. In addition, the promotion effect of supplier-customer duality on firms’ vertical specialization is mainly achieved by reducing external transaction costs, and this effect is more pronounced in production-based firms, firms with more distance from their suppliers and customers, and firms with longer duration of supplier-customer duality. Further, supplier-customer duality can resist the negative impact caused by supply-chain risks and external environmental risks. Finally,supplier-customer duality improves productivity by promoting firms’ vertical specialization.The contributions of this paper are as follows: First, it investigates the triadic relationships among suppliers, focal firms, and customers, thereby expanding the literature on supply-chain relationships. Second, it explores the impact of supply-chain triadic relationships on firms’ vertical specialization from the perspective of supplier-customer duality, adding to the literature on factors affecting firm specialization. Third, it sheds light on the bright side of supplier-customer duality, offering new insights for external stakeholders and providing empirical evidence that supports the development of a modern supply-chain system, enhances TFP, and fosters high-quality economic growth.更多还原