Background and Objectives: Tobacco companies have misused science for decades in order to protect and increase their profits. Among other things, they undertook research obscuring the harms of their products, created doubt about work that countered their interests and engaged in flawed publishing practices. Efforts to address this misconduct included rulings requiring the shut-down of scientific 3rd parties, journals refusing to publish tobacco industry-funded research, and conferences excluding the tobacco industry. In recent years, however, tobacco industry engagement in science appears to have increased. Evidence has shown, for example, the establishment of a new major scientific 3rd party and failure of industry-linked authors to declare conflicts of interest. The industry’s engagement in scientific events, including conferences, symposia and workshops, has not yet been examined. We fill this gap focusing on the two largest transnational tobacco companies, British American Tobacco (BAT) and Philip Morris International (PMI). Methods: To identify events, we collected and collated publicly available data from BAT and PMI’s websites. To assess the nature of the involvement, we extracted data from websites and materials linked to events. Results: Between April 2012 and September 2021, BAT and/or PMI employees attended 213 scientific events, mostly held in Europe and North America. Events covered a diverse range of disciplines: toxicology (28.1%), medicine (11.7%), biology (11.3%), chemistry (10.8%), aerosol science (8.5%), dentistry (4.2%), pharmaceutical science (3.8%), and computing (3.8%). BAT and PMI provided 77 presentations linked to 65 events and 356 posters linked to 118 events. Companies rarely sponsored events (n=9), acted as exhibitors (n=3) or were represented in organising committees (n=1). Conclusions: BAT and PMI were present at a large and diverse number of scientific events. The tobacco industry can use such events to (re-)build scientific credibility. This study underscores the need to address the tobacco industry’s presence in such spaces.