Abstract:     It is an important strategy for latecomers to optimize resources and catchup technologies to acquire complementary technology through cross-border M&A. This study adopted the cross-border M&A of China′s A-share listed companies as the sample and constructed the negative binomial regression analysis method to investigate the influence mechanism of cross-border M&A parties′ technology complementarity on the innovation performance of the acquirer and to analyze the moderating effect of the knowledge base of the acquirer on the relationship between the two. The results showed that there is an inverted U-shaped relationship between the technology complementarity and the innovation performance of the acquirer. An increase in the width of knowledge base exacerbates the threshold effect of the impact of technology complementarity on innovation performance, and an increase in the depth of the knowledge base reverses this inverted U-shaped relationship to a U-shaped one. In addition, through further analysis, it was found that the technology complementarity of the two sides of the cross-border M&As has an inverted U-shaped impact on the exploratory and exploitative innovation performance of the acquirer, and the breadth and depth of the knowledge base has a significant moderating effect on the above-mentioned inverted U-shaped relationship. This has broken the research limitation caused by the homogenization of firm innovation models in existing research from the perspective of ambidextrous innovation. The research conclusion will enrich the theoretical research on cross-border M&A, thus having a certain reference value for firms to better "go global".

Key words: cross-border M&A, technology complementarity, breadth of knowledge base, depth of knowledge base, innovation performance