O pen science (OS) opens up new ways of creating and sharing knowledge and of disseminating various kinds of results, such as traditional articles, research data, computational and mathematical codes, 3D models, interactive visualisations, or microinsights. Moreover, OS offers the chance to introduce new ways of evaluating science in a more nuanced, fair, and precise way. As the recent 'altmetrics' push has shown, there is wide agreement that conventional approaches to science evaluation are inadequate. With the open movement becoming stronger -especially in science -, it is a good time to reflect on potential new indicators to gauge the uptake and impact of OS. This conceptual work aims to offer a vantage point for more substantial discussions among the key stakeholders.