讲座题目：Weaponization of Trade Credit in Competitive Market: Evidence from the Paycheck Protection Program（竞争市场中贸易信贷的武器化：来自薪资保障计划的证据）

主 讲 人：李雄  中国科学技术大学

讲座时间：2025年12月18日15:00

讲座地点：学院237（金融系易方达会议室）

讲座内容摘要：

This paper examines whether firms adopted aggressive trade credit policies to expand market share during the COVID-19 pandemic. Exploiting the Paycheck Protection Program (PPP) as a plausibly exogenous liquidity shock, we implement a difference-in-differences design comparing PPP recipients and non-recipients from 2019 to 2021. We find that PPP recipients increased trade-credit provision by 1.4–2.1 percentage points relative to control firms, with no pre-trend. The expansion is concentrated among firms operating in highly competitive markets, with low pandemic exposure, and toward marginal customers with smaller size and weaker bargaining power. Consistent with aggressive liquidity redeployment, PPP recipients subsequently gained market share but at cost of short-term loss. The market-share gains stem from reduced supply-chain relationship disruptions and the acquisition of new customers. We further document significant spillover effects: rivals lost market share, while downstream customers modestly benefited. Overall, the findings suggest that public liquidity support not only stabilized firms but also reshaped product-market competition, as firms used aggressive trade-credit policies to reallocate demand and transmit liquidity along supply chains.

本文考察企业在特殊时期是否通过采取更激进的贸易信贷政策来扩张市场份额。利用薪资保障计划所带来的外生性流动性冲击，我们采用2019–2021年间PPP获得者与非获得者的双重差分设计进行识别。结果显示，相较于对照组企业，PPP获得者贸易信贷投放比例显著提高了1.4–2.1个百分点，且不存在显著的事前趋势。该效应主要集中在竞争更激烈、疫情暴露程度较低的行业，以及面向规模较小、议价能力较弱的边际客户。与激进的流动性再配置一致，PPP 获得者随后获得了更高的市场份额，但付出了短期利润下降的代价。市场份额的提升主要源于供应链关系中断的减少以及新增客户的获取。此外，我们进一步记录到显著的溢出效应：竞争对手市场份额受损，而下游客户则获得一定程度的好处。总体而言，本文发现公共流动性扶持不仅稳定了企业运营，也通过企业对贸易信贷政策的激进运用重新塑造了产品市场竞争格局，推动了需求再分配并沿供应链传导流动性。

主讲人学术简介：

李雄，中国科学技术大学管理学院和科技商学院特任副教授，硕士研究生导师。博士毕业于香港大学，曾在美国华盛顿圣路易斯大学做访问学者。主要研究领域为供应链金融。目前多篇工作论文在金融和会计的领域顶刊返修，包括The Accounting Review和Management Science (独立作者)。