Is GPT-3.5 or GPT-4 output watermarked?

Interestingly, I have found no reliable information, if output generated by GPT-3.5 or GPT-4 is currently watermarked. Does anybody know and have a reliable source for this?

I don’t think you’ll get a reliable answer any time soon unfortunately, as far as I know there’s no watermarking in place, but several news articles state that OpenAI is experimenting with the feature.