Where excludability matters: Material versus intellectual property in academic biomedical research

On the basis of survey responses from 507 academic biomedical researchers, we examine the impact of patents on access to the knowledge and material inputs that are used in subsequent research. We observe that access to knowledge inputs is largely unaffected by patents. Accessing other researchers' materials and/or data, such as cell lines, reagents, or unpublished information is, however, more problematic. The main factors associated with restricted access to materials and/or data include scientific competition, the cost of providing materials, a history of commercial activity on the part of the prospective supplier, and whether the material in question is itself a drug. © 2007 Elsevier B.V. All rights reserved.