@Jeff Jeffery
Thank you for your post and I apologize for the delayed response!
I don't believe there's a formal way to see who created your AzureAD or B2C tenant, since the "Technical Contact" can be changed. However, if the contact isn't changed, you can see the email of the user that created the tenant (AzureAD or B2C) within Azure Active Directory under Properties. If you're checking for B2C, make sure you're signed into your B2C tenant, then navigate to Azure Active Directory.
From my B2C tenant:
Since I'm a Global Admin, I'm able to change the Technical Contact info, but if you use a user that doesn't have the correct permissions, the text box will be greyed out.
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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