Keygen - A dead-simple software licensing API built for developers
ProWritingAid - For the smarter writer. A grammar checker, style editor, and writing mentor in one package.
Labs64 NetLicensing - Monetize your digital products and services
Turnitin - Turnitin is preferred by educational institutions around the world for preventing plagiarism. Instructors at all levels of education can request that students use the service to submit papers, and Turnitin checks those papers for plagiarism.
LicenseSpring - Reliable and easy to use License-As-A-Service (LaaS) for for any software application
wyDay LimeLM - Use LimeLM to add hardware-locked licensing, online activation, and timed trials to your app.