Extensive research has taken place over the years to examine the barriers of OER adoption, but little empirical studies has been undertaken to map the amount of OER reuse. The discussion around the actual use of OER, outside the context in which they were developed, remains ongoing. Previous studies have already shown that searching and evaluating resources are barriers for actual reuse. Hence, in this quantitative survey study we explored teachers’ practices with resources in Higher Education Institutes in the Netherlands. The survey had three runs, each in a different context, with a total of 439 respondents. The results show that resources that are hard or time-consuming to develop are most often reused from third parties without adaptations. Resources that need to be more context specific are often created by teachers themselves. To improve our understanding of reuse, follow-up studies must explore reuse with a more qualitative research design in order to explore how these hidden practices of dark reuse look like and how teachers and students benefit of it.