Definition of independent for the purposes of this question: source is not owned by a for-profit corporation, is not financially backed by any billionaire (either directly or via foundation or nonprofit organization) and is not financed by any national government (even if run without oversight).
It can have any perceived bias or political leaning.
Edit: Just to add it has to be written in English.
This is something else made so much worse by wealth inequality. The very wealthy have a vastly outsized influence on every aspect of the world. Being a billionaire, no matter how well-intentioned, is inherently a negative for humanity.