GPars is distributed under the liberal open-source Apache 2 License. In essence, you are allowed to use GPars on both commercial and open-source projects.
By using GPars you accept that the software is provided as is, without any further legal and other liabilities, guarantees, maintenance or support from the authors (suplier).
The authors cannot be hold liable for any defects, malfunctions or misbehavior of the software, nor for any damages caused by using it. You run the software at your own risk.