This paper shows that the features that characterize the exchange of information among individuals vary depending on the type of information exchanged (novel or specific) and the institutional affiliation of the individuals involved. It unbundles the concept of strong and weak links into three main tie characteristics: trust, friendship and reciprocity. Using data from a survey of nanotechnology researchers, we identify the characteristics of 594 links between researchers and individuals from different institutional groups (firms, governmental organizations and universities). Findings suggest behavioral regularities that are contingent on the kind of information being exchanged and the contact?s institutional membership. For, instance, when university researchers exchange novel information between themselves, the level of trust becomes essential, but exchanges with individuals from other institutional settings (firms and governmental organizations) will be characterized instead by reciprocity and friendship. We discuss the implications of these findings for research on the relational perspective of social networks and university-society relationships.