In the software industry, licensing generally falls into one of two categories; perpetual licenses i. A perpetual license, as the name implies, never expires. Someone who purchased SolidWorks 95 many years ago without subscription support could theoretically run the license in perpetuity, so long as there is a computer and operating system that are available and operational to run the software. A perpetual license with subscription support provides you access to the latest releases and service packs, technical support, Knowledge Base solutions, Customer Portal, MySolidWorks resources, etc. Perpetual licensing with subscription offers the lowest total cost of ownership over the long haul.