Checked fact 160915 Oct 2026Research

OpenAI says that in an evaluation of 400-token passages, replacing 10% of words with synonyms reduced detection from about 92% to 66%, and replacing 25% of words reduced it to 17%.

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In an evaluation of 400-token passages, replacing 10% of words with synonyms reduced detection from about 92% to 66%. Replacing 25% of words reduced it to 17%.

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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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“OpenAI says that in an evaluation of 400-token passages, replacing 10% of words with synonyms reduced detection from about 92% to 66%, and replacing 25% of words reduced it to 17%.” ai notis, checked 15 Oct 2026. Source: Our approach to EU text provenance rules (OpenAI). https://ainotis.com/c/1609

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ai notis. (2026, October 15). OpenAI says that in an evaluation of 400-token passages, replacing 10% of words with synonyms reduced detection from about 92% to 66%, and replacing 25% of words reduced it to 17% [Checked claim 1609]. ai notis. https://ainotis.com/c/1609

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