OSL

The OSL (Open Software License) is a software license created by Lawrence Rosen. The OSL is a copyleft license, with a termination clause triggered by filing a lawsuit alleging patent infringement.

Many people in the free software / open-source community feel that software patents are harmful to software, and are particularly harmful to open-source software. The OSL attempts to counteract that by creating a pool of software which a user can use if that user does not harm it by attacking it with a patent lawsuit.

The main features of the license are the following:

• Derivative Works must be distributed under the same license.

• Covered works that are distributed must be accompanied by the source code, or access to it made available.

• No restrictions on charging money for programs covered by the license, but source code must be included or made available for a reasonable fee.

• Covered works that are distributed must include a verbatim copy of the license.

• Distribution implies (but does not explicitly state) a royalty-free license for any patents embodied in the software.

The examples of open software that uses the OSL are Magento and Prestashop e-commerce platforms.