【Abstract】Although many studies employ social network theory to explain firm innovation, how individual-level factorslead to a firm's collective innovation capability remains under-researched. Building on studies that use thework boundary to define formal and informal social interactions,this research aims to illuminate how informalbuyer-supplier employee interactions influence buyer firms' innovation capabilities through knowledge acquisition.Integrating the literatures on absorptive capacity and social interaction, the analysis of survey data from273Chinese manufacturing firms suggests that employees' informal interactions are positively associated withknowledge acquisition and enhance firms' innovation capabilities. Furthermore, the indirect effects of informalinteractions on innovation capability are moderated by knowledge application.

　　【Keywords】Informal interaction; Social networking; Innovation; Absorptive capacity; Knowledge acquisition

　　*刘学元教授系本文第一作者。

　　本文于2017年2月27日发表于Journal of Business Research，该杂志为我院认定的A-类SSCI期刊。全文链接：http://www.sciencedirect.com/science/article/pii/S0148296317300723