Does ChatGPT watermark text?

OpenAI is a signatory to the EU Code of Practice on Transparency of AI-Generated Content, but has not published a text watermarking method or shipped a public detector. Reporting has indicated internal work on text watermarking that has not been released.

OpenAI does attach C2PA provenance metadata to images generated by DALL·E and its successors. That is file-level metadata, not a text watermark, and it does not survive copying text out of a conversation.