This paper contributes to the scarce volume of studies of mergers involving family businesses. In the merger described, managers used the culture concept to name problematic aspects of the integration process. In the analysis, we have used the three-circle model to understand the contradictions that emerged in the managers description of organizational culture. To consider the subsystems in the three-circle model: ownership, business and family, means a broadening of the idea that the founder (family) shapes the organizational culture. This could be especially relevant for larger and/or growing family businesses.