Only parts (non-core) of QT are GPL, most are LGPL And it's a bit of a misconception that LGPL requires statically linked things to be open sourced: in that ar

Only parts (non-core) of QT are GPL, most are LGPL And it's a bit of a misconception that LGPL requires statically linked things to be open sourced: in that area it only requires that the LGPL components be replaceable (and the source for the LGPL components be available). In the context of static linking, that can be done by releasing pre-link binaries (object files) with instructions for linking them. Of course, that's likely more work than just making the source available under a proprietary license (ie: provide source code so LGPL components can be replaced). If you're using Qt GPL components, then yes, you'll need to open source your application (or pay for a Qt License)