Abstract: Methods and systems for enforcing license requirements with respect to the installation of software updates are provided. In particular, the installation of a software update requires that the system running licensed software hold a license with a validation date that is the same as or later than a publication date associated with the software update. The validation date in the license file and the publication date associated with the software update are protected against unauthorized alteration. Software updates can be installed at a date later than the validation date in the license file, so long as the validation date is not earlier than the publication date of the software update.