**Hypothesis 1 (H1).** *TMT functional experience heterogeneity is positively related to innovation quality.*

TMT industry experience represents the familiarity and sensitivity of team members to regulations, opportunities, threats, competitors, and industrial chains in the sector [10], which is a unique human capital that those outside the sector do not possess. However, TMT industry experience heterogeneity may diminish the enterprise's understanding of market change and knowledge base, which would lower the enterprise's ability to innovate [46]. First, the senior executives' inability to fully comprehend the current industry due to their experience working across multiple sectors makes it difficult for TMT to accurately identify market opportunities, perceive market changes, and comprehend the underlying changes taking place in the sector, all of which affect the quality of innovation decisions. Second, because high-quality innovation is characterized by specialization, refinement, and novelty [47], enterprises need to enhance vertical knowledge innovation and creativity, concentrate knowledge, human resources, and other resources to develop new technologies and vigorously develop specialized production. For this reason, many enterprises employ executives with extensive industry knowledge. They make sound decisions for high-quality innovation since they are knowledgeable about industry regulations and technological trends. On the contrary, frequently changing the industry in which they work makes senior executives lack professional knowledge and a unique perspective on the industry. Due to their lack of industry experience, they are not only unable to acquire and integrate resources in a more targeted way to meet the needs of high-quality innovation [48], but they also find it difficult to point out the direction for improving innovation quality. Together, these arguments suggest that TMT industry experience heterogeneity may hinder the improvement of enterprise innovation quality. Therefore, we propose the second hypothesis: Hypothesis 2.

#### **Hypothesis 2 (H2).** *TMT industry experience heterogeneity is negatively related to innovation quality.*
