xQuiD Core is available under the LGPL version 3 license. Since the LGPL is a set of additional permissions on top of the GPL license, to know all license terms and conditions related to this license model you have to read the GPL license text and the LGPL license text.
Essentially, under this license model you may:
Under this license terms you are not allowed to:
For now, xQuiD plug-in for Eclipse is not open-source although it can be distributed, downloaded and used "AS IS".