Descriptive statistical results of the variables.

As an important means for enterprises to acquire technological resources, the impact of mergers and acquisitions on technological innovation and underlying mechanisms deserve in-depth study. Using the merger and acquisition data of A-share listed Chinese companies from 2007 to 2020 in Shanghai and Shenzhen, the causal effects and influence mechanisms between mergers and acquisitions and technological innovation are identified and tested using the Difference-in-Differences method. The study finds that mergers and acquisitions have a long-term, sustained, technological innovation-enhancing effect on firms. Mechanism tests show that mergers and acquisitions can promote the technological innovation of enterprises by improving production efficiency, enriching digital knowledge, and enhancing market power. A heterogeneity analysis shows that the effect of mergers and acquisitions in enhancing technological innovation is more significant when the mergers and acquisitions meet domestic merger and acquisition requirements, when there is a small transaction size, and when the enterprises involved in the mergers and acquisitions are not state-owned. It is suggested that enterprises and the government should use multiple measures, while considering the impact of heterogeneity, to take full advantage of the positive effects of mergers and acquisitions on technological innovation.作为企业获取技术资源的重要路径，并购对企业技术创新的影响及其内在作用机制值得深入探究。本研究依托2007至2020年沪深两市中国A股上市公司的并购数据，采用双重差分法（Difference-in-Differences）识别并检验了并购与企业技术创新之间的因果效应及作用路径。研究结果表明，并购对企业技术创新具有长期且持续的提升作用。作用机制检验结果显示，并购可通过提升生产效率、丰富数字化知识储备以及增强市场势力，促进企业技术创新。异质性分析结果表明，当并购为国内并购、交易规模较小且参与并购的企业为非国有企业时，并购对技术创新的提升效应更为显著。据此建议企业与政府多措并举，同时充分考量异质性影响，以最大限度发挥并购对企业技术创新的积极作用。