Research on the value of personal relationships to distant locations (bridging ties) for innovation has yielded mixed findings. This paper proposes that part of these empirical inconsistencies is due to the ambiguity of the concept of advice tie. Based on knowledge search theories, it draws a distinction between advice ties serving surface knowledge search and those serving deep knowledge search. We theorize that the effect of bridging ties is contingent to the type considered: bridging ties have a positive impact on individual patent performance when they serve deep knowledge search, and negative when they serve surface knowledge search. Data from 140 R&D engineers at a French cluster in nanotechnologies provides evidence for our hypotheses.
