Getting Key Text BBBBB-BBBBB-BBBBB-BBBBB-BBBBB instead of Windows Serial number on some servers
The most common reason is that the servers have been deployed under a "Volume License" agreement.
Let us know if this is not the case.
I think the MS article discusses it:
http://answers.microsoft.com/en-us/windows/forum/windows8_1-windows_install/product-key-shows-as-bbbbb-bbbbb-bbbbb-bbbbb-bbbbb/9daa65ce-2fa8-48fc-8373-066940b384f6
We also have a page on our wiki about this - Information about software keys
Getting Key Text BBBBB-BBBBB-BBBBB-BBBBB-BBBBB instead of Windows Serial number on some servers