Microsoft software demystified: What EU buyers need to know

Microsoft software licensing is complex, with activation keys not guaranteeing legal entitlement, and buyers must ensure compliance, especially when purchasing secondary licenses in the EU.

Buying Microsoft software may appear straightforward: you purchase a key, activate the product, and start working. In reality, Microsoft licensing is far more complex. Misunderstandings about activation, legal entitlement, distribution channels, and resale rights can expose companies to compliance risks – particularly within the European Union. As explained in our webinar:

We would like to demystify, we would like to clarify certain misunderstandings, we'd like to clarify certain myths surrounding Microsoft products.

Understanding how licensing actually works is essential for making safe and informed purchasing decisions.

Product key is not a license

One of the most widespread myths is that a product key and a license are the same thing. They are fundamentally different.

A product key is a technical activation tool – typically a 25-character alphanumeric code used to unlock software. Its purpose is purely technical: it allows installation and activation of the product. A license, however, is a legal entitlement. It is the contractual right to use the software under specific terms and conditions defined by the publisher. It determines who may use the software, on how many devices, and in what manner.

The key itself does not license, does not grant you the right to work with the software. It does not legalize your usage.

A simple analogy illustrates this clearly: the product key is like a house key, while the license is the deed proving legal ownership. You may unlock the door with the key, but without the deed, you do not legally have the right to occupy the house. Activation alone does not equal compliance.

Cheap keys, online marketplaces and hidden risks

Many buyers assume that if software activates successfully, it must be legal. That assumption is incorrect. The legality of software depends on the source of the license, the licensing channel, and whether proper usage rights were transferred. When purchasing directly from Microsoft or authorized partners, licenses are delivered via official management portals such as the Microsoft 365 Admin Center and assigned to the customer’s tenant.

However, online marketplaces frequently offer extremely cheap product keys. These keys may activate, but activation does not guarantee legality. As clearly stated in the webinar:

Purchasing your product key and having this key activated does not mean that you are legally covered.

Some of these offers originate from geographically restricted markets where different pricing policies apply. Others involve developer keys intended only for testing or internal development. There are also cases involving unauthorized internal distribution or even fraudulent acquisition. Even if technically functional, such licenses may later be revoked or found non-compliant.

Significant price differences should therefore be treated with caution. New Microsoft perpetual licenses are not realistically sold at a fraction of the official price for commercial customers. When an offer appears too good to be true, it usually requires closer scrutiny.

Secondary software in the EU: When is it legal?

Within the European Union, secondary (used) perpetual licenses can be legally resold – but only under strict conditions. The license must be perpetual rather than subscription-based, meaning time-limited subscriptions such as Microsoft 365 cannot be transferred. The original owner must uninstall and deactivate the software and provide a legally binding declaration confirming this. The license must have been fully paid for, and it must originate from the EU or European Economic Area. Licenses first placed on the market outside this region cannot be imported and resold as EU secondary licenses.

Proper documentation is essential to demonstrate compliance. Although there is no single legally prescribed checklist, best practice includes declarations from the original owner (and any intermediate owners, if applicable), confirmation of deinstallation, proof of EU origin, and transaction records. An invoice alone does not prove legality; it merely confirms that a transaction occurred. Compliance depends on whether all legal conditions for transfer are fulfilled and documented.

It is also important to understand delivery differences. New perpetual CSP and Volume licenses are assigned to a customer’s Microsoft tenant through official portals. Secondary licenses, however, are not assigned to Microsoft management platforms. Instead, buyers receive product keys, installation access, and the required legal documentation. Portal assignment is not legally required for secondary perpetual licenses, provided all EU conditions are satisfied.

Microsoft licensing is more nuanced than many organizations expect. A product key unlocks software, but only a license grants the legal right to use it. Activation does not automatically guarantee compliance, and both buyers and sellers share responsibility in ensuring legality. For EU businesses, especially those considering secondary perpetual licenses, understanding the rules, verifying documentation, and recognizing warning signs are essential steps toward secure and compliant software procurement.

Would you like to learn more? Watch our webinar! Link here: Microsoft Software Demystified: What EU Buyers Need to Know