Eclipse Public License
Overview
The Eclipse Public License (EPL) is an open-source software license used by the Eclipse Foundation for its software. It replaces the Common Public License (CPL) and resolves some minor issues with that license. The EPL is a copyleft license that requires the distribution of the source code, including any modifications, with the software.
History
The EPL was first released in 2004 by the Eclipse Foundation, which was established by IBM to manage the development of the Eclipse Integrated Development Environment (IDE). The license was designed to be more business-friendly than other open-source licenses, while still ensuring that contributions to the software are shared with the community.
Terms and Conditions
The EPL grants the rights to use, copy, modify, and distribute the software and its source code, subject to certain conditions. These include the requirement to make available the source code of any modifications or derivative works, and to license these under the EPL. The license also includes a patent grant, which grants the licensee the rights to any patents held by the licensor that are necessary to use the software.
The EPL does not require that derivative works be licensed under the EPL, but it does require that the source code for any modifications be made available. This allows for the creation of proprietary software that uses EPL-licensed software, as long as the modifications to the EPL-licensed software are made available under the EPL.
Comparison with Other Licenses
The EPL is similar to other copyleft licenses in that it requires the distribution of the source code, including any modifications. However, it differs from licenses such as the GNU General Public License (GPL) in that it allows for the creation of proprietary software that uses EPL-licensed software, as long as the modifications to the EPL-licensed software are made available under the EPL.
The EPL is also similar to the Mozilla Public License (MPL) in that it includes a patent grant and allows for the creation of proprietary software. However, the EPL is more business-friendly in that it does not require that the entire software be made open-source, but only the parts that are EPL-licensed.
Criticisms and Controversies
While the EPL is generally well-regarded in the open-source community, it has been criticized for its complexity and for being less business-friendly than other open-source licenses. Some critics argue that the EPL's requirement to distribute the source code of modifications can be burdensome for businesses, and that it can be difficult to determine what constitutes a modification under the EPL.
Adoption
The EPL is used by a number of high-profile open-source projects, including the Eclipse IDE, the Jetty web server, and the Equinox OSGi framework. It is also used by a number of companies for their open-source projects, including IBM, Google, and Red Hat.