The green and digital transitions (twin transitions) are reshaping the global business environment, yet academic research exploring the financial implications of the green-digital nexus remains limited. This paper explores the financial implications of a key mechanism within the green-digital nexus, technological connectedness through knowledge creation and spillovers. Quantified through patent data between 2010 and 2022, this study examines how tech firms' financial performance is affected by knowledge creation and spillovers to green (technologies related to clean energy) and brown (technologies related to fossil fuels) domains using portfolio- and firm-level analyses with panel data regression models. The results indicate that financial connectedness is not straightforward, contrary to findings from aggregate level studies in the literature. While firm-level heterogeneity in knowledge creation does affect returns, there is no conclusive evidence that knowledge spillovers affect financial performance. • The green and digital transitions are shaping the global business environment. • This paper examines how tech firms' financial performance is affected by knowledge creation and spillovers. • The results indicate that the financial implications of the green-digital nexus are not straightforward. • Knowledge creation affects the impact of external factors on firms' returns. • However, there is no statistically significant evidence for knowledge spillover.