How does Microsoft know my full legal name?

Hello. In apps such as Outlook or email suggested fields, Microsoft may display your complete legal name (including middle names) based on how your identity was verified or synced across Microsoft Services. This generally occurs when Microsoft setup your account using personal identification, a payment source, or a school/work account that may be included in the organization's directory as it contains your full name. Even if you never saved a contact with your full name in your contacts list manually, Microsoft can source your full name from your account's metadata, email messages in headers, or a profile from a synced device.

Deleting a contact suggestion from a suggested contact does not remove the underlying identity data as it remains records within Microsoft identity systems. To limit this experience from happening repeatedly, visit account.microsoft.com and review your profile and “Your Info” to limit how Microsoft has set up or configured your display name. Also review any organization accounts that may be connected and view metadata in Office documents that may show your full name. Microsoft does not officially disclose all internal sources of identity data but its systems are designed and developed to validate user identity across Microsoft Services to ensure consistency, a form of triaging and provide utilitarian purposes of security.

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