If you already have a legal installed version of Autodesk software and are interested in purchasing a license of a newer version, you may be eligible for an upgrade. In many cases, upgrades are available at a lower price than new seats. To qualify for an upgrade to a 2015 version, you must be moving from a 2009 or more recent version. You will need to provide the serial number for the license you're currently using when you register your new purchase. To purchase an upgrade, simply search for the upgrade of the software you are interested, in or look for a link to the upgrade at the right side of the product description page for that software.