<p>Growing presence of large technology firms (Big Tech) in frontier research has recently raised significant concerns about control over scientific knowledge production and critical technologies. These firms now command unparalleled access to key inputs of innovation, data, talent, computational capacity, and capital, allowing them to increasingly displace traditional public research institutions. While these concerns have been strongly expressed by prominent scholars, validation of such concerns have not fully materialized. More crucially, there is emerging evidence that Big Tech’s influence on research has been overtly exaggerated. To critically assess these competing claims, this study examines Big Tech’s power in the production of scientific knowledge through frontier research, particularly in critical and emerging technologies (CETs), such as artificial intelligence, quantum computing, and biotechnology. Using bibliometric data from OpenAlex on 3.28 million publications on CETs between years 2001 and 2024, we document the publication of research outputs authored or co-authored by Big Tech-affiliated scientists. We further zone in on one vital critical technology – artificial intelligence (AI) and assess Big Tech’s extent and nature of influence on AI research. We find mixed evidence of presence of Big Tech in CETs research and increasing presence of Big Tech in AI research. We also find that collaborative research between Big Tech and other knowledge institutions is associated with higher research impact and higher probability of publications to include keywords related to trustworthy AI. The findings contribute to ongoing debates about technological sovereignty, epistemic capture, and the geopolitical risks associated with the privatization of critical knowledge infrastructures.</p>