JpGraph is released under a dual license. For non-comercial usage the library is released uner QPL 1.0 (Qt-License) and under the JpGraph Professional License for commercial use. Commercial use is defined as either a) The library is included as an integral part of a product that is sold with a cost that exceeds the cost of the distribution medium. b) The library is offered as a WEB service for a fee c) The library is used on an intranet in a company with more than 5 employees