Software revalidation. In one example embodiment, a method for software revalidation may include various steps. For example, the method may include receiving, at a machine on which a software application has been installed and activated, activation rules that have been updated since release of the software application. The method may also include periodically applying, at the machine, the updated activation rules to newly-collected machine configuration information from the machine to determine whether a product key remains valid for the newly-collected machine configuration information and, in response to determining that the product key remains valid for the newly-collected machine configuration information, revalidating, at the machine, the software application to authorize continued access to the software application.