Open Innovation has emerged as a critical model for fostering innovation in startups, driving their social, economic and technological growth. However, the implementation and outcomes of Open Innovation in specific startup ecosystems, such as the Sururu Valley hub in the city of Maceió (Alagoas state, Brazil), remain underexplored. This paper aims to analyze two startups based in the Sururu Valley hub, named Trakto and Amitis, examining how the Open Innovation strategies contribute to their development. A comparative case study methodology was employed, focusing on the startup adoption of inside-out and outside-in innovation processes. Central question answered through this research is how these enterprises are benefiting from these Open Innovation practices and ecosystems to survive and grow. The results indicate that in spite of both businesses share coupled process characteristics, Trakto predominantly relies on external knowledge absorption (outside-in innovation), and Amitis leverages its internal knowledge by sharing it with external stakeholders (inside-out innovation). These findings highlight the diverse ways Open Innovation can support startup growth and emphasize the importance of tailored innovation strategies within collaborative ecosystems.