ProWritingAid - For the smarter writer. A grammar checker, style editor, and writing mentor in one package.
Keygen - A dead-simple software licensing API built for developers
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.
Labs64 NetLicensing - Monetize your digital products and services
LicenseSpring - Reliable and easy to use License-As-A-Service (LaaS) for for any software application
Unicheck - The plagiarism checker Unplag scans across the internet, repositories, open sources content and databases. It delivers real-time results and has no cached data.