PTC provides legal, free-to-use versions of its software for specific audiences:
: A free viewer for opening and visualizing 3D CAD models without needing a full license. How to Access the Free Download PTC Creo 6 Free Download
: a "free-for-life" version of their direct modeling software, ideal for quick 3D designs and one-off projects. PTC provides legal, free-to-use versions of its software