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The Qt Commercial Developer License is the appropriate version to use for the development of proprietary and/or commercial software.
This version is for developers who do not want to share the source code with others or otherwise comply with the terms of the GNU Lesser General Public License version 2.1 or GNU GPL version 3.0.

This version of Qt is appropriate for the development of Qt applications (proprietary or open source) provided you can comply with the terms and conditions contained in the GNU LGPL version 2.1.

This version of Qt is appropriate for the development of Qt applications where you wish to use such applications in combination with software subject to the terms of the GNU General Public License version 3.0 or where you are otherwise willing to comply with the terms of the GNU General Public License version 3.0.