LibreCAD - An open source 2D CAD application for Windows, Apple and Linux.
Quick License Manager - Quick License Manager (QLM) is a license protection framework that creates professional and secure license keys to protect software against piracy.
FreeCAD - An open-source parametric 3D modeler
Labs64 NetLicensing - Monetize your digital products and services
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LicenseSpring - Reliable and easy to use License-As-A-Service (LaaS) for for any software application