OpenAI is rolling out an invisible, machine-readable watermark for its ChatGPT and Codex text outputs, but the feature is initially available only to users in the European Union.
The company claims its textGrain watermarking "matched or exceeded" other approaches, such as Google DeepMind’s SynthID, which is also the foundation for Anthropic's watermarking method. Both moves aim to comply with the EU's AI Act; however, the announcement has met with some dissatisfaction.
OpenAI has included benchmark scores demonstrating that watermarked and unwatermarked text perform similarly. The company acknowledges that textGrain "does not guarantee reliable detection" and clarifies that watermarks do not verify accuracy, determine ownership, measure human contribution, or prove human authorship.
Rolling out text watermarking in the EU. Over the coming weeks, text watermarking will be introduced to eligible ChatGPT and Codex users across all subscription plans within the EU. The company is deliberately not making this a global default at launch, preferring to learn from real-world use and feedback in a specific region first.
Enabling opt-in watermarking for API customers. Beginning today, API customers worldwide will have the option to enable watermarked text outputs for specific models. This allows clients to manage their transparency obligations and user experiences according to their specific needs. OpenAI is also collaborating with cloud partners to make watermarking available for model outputs accessed through their services in the upcoming weeks.
Providing detector access to researchers and expert organizations. Researchers and expert organizations can submit applications starting today. In alignment with the Code of Practice, access will be granted on a case-by-case basis to facilitate the evaluation and improvement of text provenance. The tool will indicate whether an OpenAI watermark is detected without exposing user identities or revealing prompts or conversations. Due to the potential for missed watermarks and false positives, the tool will not be made publicly available at this time.
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