<p>Universities are increasingly tasked with fulfilling a “third mission”—driving economic growth through knowledge creation and innovation, with inventive activities serving as an important mechanism to achieve this mission. This research investigates the link between workforce age diversity and the intensity of inventive activities in universities to enhance our understanding of how demographic characteristics are associated with innovation and, ultimately, contribute to economic growth. Workforce age diversity is proposed to be linked to inventive activities via two distinct yet competing mechanisms: on the one hand, workforce age variety should facilitate collaboration, knowledge sharing, and networking, all of which should enhance invention; on the other hand, workforce age polarisation tends to result in social categorisation, lower trust, and affective conflict, which should hinder invention. Using the UK higher education sector as the empirical context, the analysis reveals a positive association between workforce age variety and the intensity of inventive activities in universities, as seen from more invention disclosures and patent registrations. Conversely, workforce age polarisation shows a negative association with the intensity of inventive activities, which is evidenced by fewer patent applications and registrations. As such, this research contributes to the literature by highlighting the important but nuanced link between workforce age diversity and the intensity of inventive activities. It also offers practical and policy implications aimed at promoting an age-inclusive invention process in universities.</p>