Hello @David Thielen ,
Welcome to Microsoft Q&A!
If you are a Microsoft Partner and have already created a partner account, you can find your MPN/partner ID in the Partner portal under View Account > Partner Profile > Organization Profile > Identifiers.
If you have not yet created a partner center account, you can do so by following the steps in MPN Create a Partner Center Account. Once you have enrolled you will see your details in the Partner Center.
You will need to associate your tenant in your Partner Center account. The MPN (ID) account must be the Partner global account (PGA) for your organization, not location.
Then you need to mark your app as publisher verified by following the steps in Mark App as Publisher Verified. In order to do that, you need to make sure that you have met the prerequisites in the article. You must be signed in using MFA with an account that has the Application Admin, Cloud Application Admin, or Global Admin role in Azure AD and the MPN Admin, Accounts Admin, or Global Admin role in the Partner Center.
See also:
1.https://learn.microsoft.com/en-us/answers/questions/1118699/how-to-get-mpn-id-for-multi-tenent-app
Thank you
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