One WishList Member license can be used to activate WishList Member on one URL at a time.
If a WordPress site has the WishList Member plugin installed, it can be activated with a License Key.
This also applies to sub-domains, sub-folders, etc. For example, if WordPress is installed on a sub-domain, the WishList Member plugin can be installed and activated with a License Key.
So if you want to activate WishList Member on three URLs at the same time, you would need a three site license.
That being said, if you just need to activate a test or development site, there is an option.
A URL that begins with either of the following does not count against the WishList Member license total.
And URLs ending in the following do not count against the WishList Member license total:
For local host sites the following examples do not count against the WishList Member license total.
This means that a development or test site can be set up and does not count as a use of a WishList Member license.
The WishList Member license key must still be used to activate the test/development URL, but it will not count against the WishList Member license total.
This allows for testing on the test/development site while the live site can also use the WishList Member license key.