@Erwin Gerlich Thanks for posting in our Q&A.
For this issue, I have seen someone reported it. It seems an issue. Generally, if we can see the bios-version in intune portal, we will see it via Graph. Honestly, I couldn't repeat this situation because the Bios-version shows null in my intune portal and also shows null via Graph.
Please understand that graph issue is more related to develop scope. With Q&A limitation resources, it is suggested to create a support ticket to get more accurate help. Here is the support link:
At the same time, I will feedback this issue.
Thanks for your understanding.
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