Hi Richard, welcome and thank you for your question. My name is ***** ***** I am glad to assist you today.
To answer your question, Microsoft does not have a tracking mechanism to verify of the home edition is being used for business or in a business environment. However, the business edition has some additional features that is intended or will be useful for businesses. So if one of the 5 users use it for business, the only way that Microsoft will know that is when someone visits the office of that business and then see an MS Office "Home" edition installed which is considered a mis-licensing.
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