Clarification regarding no of vms per subscription

Hello

We run vmware servers with Linux guests

In
http://www.redhat.com/resourcelibrary/articles/articles-red-hat-enterprise-linux-purchasing-guide#note1

"Red Hat Enterprise Linux

Red Hat Enterprise Linux subscriptions are sold on a socket-pair or virtual-instance basis, depending on what makes the most sense to count. They are stackable, so you can use them like building blocks. For example, 1 subscription covers a socket–pair or 2 virtual instances. 2 subscriptions cover 2 socket–pairs or 4 virtual instances."

Does this mean I only need one subscription for 2 vms, or does this only apply to redhat servers running vms?

Best Regards

Dean Scothern