Most parts of the source for the DFRefactor tool are licensed under the LGPL license.

In other words, if you make changes/improvements then please donate the changes back to the community.

The Scintilla DataFlex wrapper is licensed via the 2 clause BSD license (Scilexer.pkg and Scilexer.h)
More free so that you do not have to worry about including it in any type of software be it commercial or not.

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