OpenAI announces eligible EU text watermarking and API opt-in
Watermarking is rolling out regionally, while the initial text detector is restricted to approved researchers and expert organizations.
- Event or announcement
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What happened
On October 5, 2026, OpenAI announced a coming-weeks rollout of invisible watermarks for eligible ChatGPT and Codex text across plans in the EU. It is not a worldwide default. API customers worldwide can opt in for selected models; API watermarking remains off by default.
Initial access to OpenAI’s text detector requires approval for researchers or expert organizations. OpenAI warns that editing and short passages can undermine detection, and that false positives and missed watermarks are possible.
The policy context
The European Commission’s guidance distinguishes providers’ machine-readable marking duties from deployers’ disclosure duties for specified uses. Technical feasibility and exceptions matter. Article 50 transparency provisions apply from August 2, 2026; that does not mean every piece of AI-assisted text requires identical treatment.
What to do with this
Editorial suggestion: Record which tool produced a passage and how it was edited. Do not treat a detector result as proof of authorship, accuracy or misconduct. For a workplace deployment, ask your compliance owner to check the applicable use case and disclosure rules; this brief is not legal advice.
Read the sources
- OpenAI: Our approach to EU text provenance rules (opens in a new tab)
- European Commission: Navigating the AI Act (opens in a new tab)
This is a source-based summary. Product performance and account access have not been independently tested here. Practical suggestions are editorial.