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Currently, libpredict is licensed as GPLv2+. That's not optimal for a library, so we want to change it to something more library friendly, e.g., LGPL. It's going to be a while before we can do so, but it is a long term goal.
In order to do that, we must do several things, like replace all the GPLv2+ code. When that is done, we can relicense the library, but only if we have the right to do so. There are several ways of achieving this, but we've chosen to use a contributor agreement that gives Akademisk radioklubb (LA1K) rights to the code. If you create a pull request, you will be asked to confirm that your contribution is submitted under this contributor agreement.
You can find the text of the contributor agreement at https://gist.github.com/la1k-admin/18d0510aa3dbe0db1b8f86e6b46c20bd
Short summary: You allow Akademisk radioklubb to use the code, but without taking away your right to also use the code as you please.