Knowing what customers want and how they use products contribute to company's innovativeness. Absorptive capacity (ACAP) is one theoretical construct that explains how companies gain information about customers and how such information is applied into practice. Yet, empirical evidence on the relationship between ACAP and knowledge from customers is still lacking. This study proposes and tests if customer collaboration is supported by ACAP and mediates the effect of ACAP on innovation performance. An established and previously validated second-order construct of ACAP is suggested to test these hypothesised relationships. Structural equation modeling (SEM) is applied to a sample of 120 selected gazelle companies that have had stable growth rates during the past three years to analyse the proposed relationships. The main finding of the study is that customer collaboration mediates the effect of ACAP on innovation performance.