Hi @Berghegen, Nick ,
Thanks for reaching out.
I understand you are looking to combine data from multi-tenant in Microsoft 365 defender to manage at one place for security reasons.
You can register an application in Microsoft Entra as multi-tenant application and call Microsoft Defender API in each tenant to collect data from each of the tenants and report that to PowerBI table as well. However, combining Microsoft Defender API information from multiple tenants into a single Power BI table can be a complex task, as it involves integrating data from various sources and dealing with authentication issues.
Alternatively, Microsoft 365 defender provides you to directly manage "multi-tenant management in Microsoft 365 Defender" which allows a unified view of all the tenants you manage which helps to streamline threats due to security reasons in single window.
Reference - https://video2.skills-academy.com/en-us/microsoft-365/security/defender/mto-overview?view=o365-worldwide
Set up multi-tenant management -https://video2.skills-academy.com/en-us/microsoft-365/security/defender/mto-requirements?view=o365-worldwide
Hope this will help.
Thanks,
Shweta
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