This report presents six case studies conducted under Task 3.2 of the PathOS project, exploring Open Science (OS) impact indicator implementation within specific disciplinary, institutional, and national contexts. Drawing on the PathOS Indicator Handbook and key impact pathways frameworks, the studies generate empirical evidence of how OS practices relate to measurable scientific, societal, and economic effects. The six cases examine diverse contexts, national repository infrastructures, thematic research platforms, field-specific dynamics, crisis response scenarios, and cross-platform usage patterns, revealing that OS impacts are highly context-dependent and not uniformly positive. Significant disciplinary variations emerged, particularly between biomedical and social science contexts, where data practices, usage patterns, and measurement challenges differed substantially. The studies also advanced methodological approaches for OS evaluation, developing new indicators and computational tools while demonstrating both the potential and limitations of algorithmic approaches for capturing impact across different research domains.