When you buy FoCal you are buying a single user license to use the software. This license grants the following:
*In order to support equipment changes you can add and remove registered cameras on your license quickly and easily. There is a limit to the number of times you can update the license before having to contact us, it’s enough to cover many years of upgrades for an average user
When you purchase FoCal you are entitled to 12 months of software updates from your date of purchase. This includes the currently released version of FoCal and all software updates (both major and minor) released over the following 12 months.
The included updates period is also tied in to the comparison data within FoCal Pro. FoCal Pro allows users to compare their results with other FoCal users around the world while they are within their included updates period.
For more information on what is included and how to renew your Included Updates Period if expired, please see this FoCal FAQ entry.