Checked fact 160815 Oct 2026Research

OpenAI says that at a target false positive rate of 1%, its detector identified watermarks in about 80% of 200-token passages, compared with about 95% of 400-token passages, for content such as psychology, and detection was substantially lower for content such as mathematics.

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At a target false positive rate of 1%, our detector identified watermarks in about 80% of 200-token passages, compared with about 95% of 400-token passages, for content such as psychology. Detection rates were substantially lower for content such as mathematics, where there is less flexibility in word choice.

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Our approach to EU text provenance rules
OpenAI · 2026-10-05

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Checked by the notis newsroom on 15 Oct 2026, against the source above.

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How text watermarks work and what EU Article 50 requires 15 Oct 2026

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“OpenAI says that at a target false positive rate of 1%, its detector identified watermarks in about 80% of 200-token passages, compared with about 95% of 400-token passages, for content such as psychology, and detection was substantially lower for content such as mathematics.” ai notis, checked 15 Oct 2026. Source: Our approach to EU text provenance rules (OpenAI). https://ainotis.com/c/1608

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ai notis. (2026, October 15). OpenAI says that at a target false positive rate of 1%, its detector identified watermarks in about 80% of 200-token passages, compared with about 95% of 400-token passages, for content such as psychology, and detection was substantially lower for content such as mathematics [Checked claim 1608]. ai notis. https://ainotis.com/c/1608

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