Following a seven-month investigation, the European Commission has reached a preliminary decision that Amazon’s and Microsoft’s cloud platforms — AWS and Azure, respectively — should be classified as “gatekeepers” under the EU’s Digital Markets Act (DMA), Reuters reports.

The DMA, also known as the Digital Markets Regulation, aims to limit the market power of dominant players. For cloud services, this would entail, among other things, requirements for increased interoperability and data portability, as well as restrictions on how these services might favor their own products and services.

The Commission pointed, among other things, to AWS and Azure’s large market shares, extensive investments, large customer bases, and high costs for customers who wish to switch providers.

If the decision is approved, the companies would be subject to the same type of regulations that apply to several of the largest technology platforms. Both Amazon and Microsoft were critical of the assessment. Amazon argued that the EU already regulates the cloud market through the Data Act, while Microsoft believes the EU is underestimating the growing competition from Google Cloud.

Amazon and Microsoft will have the opportunity to respond to the European Commission’s preliminary conclusions before a final decision is expected later this year.