Frequently Asked Questions
What is "dual licensing" of open source software?
Dual licensing is a business model available to the original owners of the copyright in an open source software system that is provided under the GPL. It is based on the concept that the original copyright owners of a software system have the right to offer the system under two (or more) different licenses if they choose. This right is a byproduct of common law relating to copyright and licensing. NB: Dual licensing is only available to the original copyright holders of software code — you cannot offer dual license to someone else's open source software.
This becomes relevant where, for example, a third party commercial software company wishes to integrate a GPL software system into a software product that they distribute. Under the requirements of the GPL, the third party commercial software company would be required to release their own commercial product as open source software under the GPL. While in some cases the commercial company may be prepared to do this, in many cases this may be against their commercialisation plans for their own software.
In this case, the third party commercial company could approach the copyright holders of the open source software and request an alternative license to the GPL. The open source copyright holders may then choose to provide a license other than the GPL to the commercial company, and this alternative license may not require the commercial company to make their own product available under the GPL if it is integrated with the open source software and distributed. In exchange for this alternative license, the open source copyright holders may choose to include additional license requirements, such as a requirement that the commercial company pay a license fee for gaining access to the software under the alternative license.
The dual licensing model is becoming one of the standard business models for open source software that uses the GPL. Companies such as MySQL (the world's leading open source database provider), TrollTech and SleepyCat use dual licensing. LAMS has adopted this model to achieve the twin goals of providing commercial providers with an option to take advantage of LAMS without requiring them to make their own software available under the GPL; and providing a potential revenue stream to assist with the ongoing development of the LAMS software.
The ultimate purpose of the use of dual licensing by LAMS is to help create a sustainable long term model for LAMS based on its adoption by both open source and commercial software providers, and the use of fees from non-GPL licenses to continue to develop the system. If you are a commercial software vendor and are interested in a non-GPL LAMS license, please contact info@lamsinternational.com.