Short answer: 20 licenses on a single "admin" email account
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Long Answer:
If you are a business Office Administrator it is best to use an "Admin" account to install and activate one-time payment Office 2019 at work to keep control of the license. If you allow the user to use their corporate
email account you will lose the associated Office license when the employee leaves the company and their
email is disabled.
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When you do the install and activation keep a record of the full product key, computer ID, admin email account
used to activate it and optionally the password on the email account.
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When you view the licenses associated with the admin account only the last 5 char of the product key is displayed.
You use that to find the full key in your records.
Note: these keys are displayed sorted alphabetically, NOT in install order.
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There is no official MS documentation that I've seen listing a specific number. The suggestion to limit to 20
is based on reports from users. They've done 20 successfully, and some have reported problems with higher
numbers.
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