Staging/Local/Dev environments are automatically excluded from the total activation count if the URL matches a specific pattern. Examples include: localhost, 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16, *.dev, .*local, dev.*, staging.*
For instance, if you use the Plus license and you have 3 live websites and each has its own staging version, you can activate the license and get updates from the Dashboard on all 6 WordPress installations. In the system, it will count that you activated the license only on the 3 live websites.
Click here to read more about how this works and the list of patterns that are used to identify a test website