Nowadays, the adoption of Open Source Software (OSS) by organizations is becoming a strategic need in a wide variety of application areas. Organizations adopt OSS in very diverse ways. The way in which they adopt OSS affects and shapes their businesses. Therefore, knowing the impact of different OSS adoption strategies in the context of an organization may help improving the processes undertaken inside this organization and ultimately pave the road to strategic moves. However, there is a lack of support for assessing the impact of the OSS adoption over the business of the adopter organizations. Based on the goal-oriented characterization of some OSS adoption strategies, in this paper, we propose a preliminary approach to assess the business impact of the OSS adoption strategies over the adopter organizations. The proposal is based on the Business Model Canvas and graph theory notions to support the elicitation and assessment of the impact of each goal over the adopter organization. We illustrate the application of the approach in the context of a telecommunications company.