OpenAI's own numbers for its EU text watermark: 92% detection on a 400-token passage, 66% after you swap 10% of the words, 17% after 25%. So the AI Act's transparency tool loses to a thesaurus and a little boredom.
The detector is also limited to approved researchers at launch, so you can't check anything yourself. The only people it will reliably catch are the ones who didn't edit, which is to say the ones who weren't hiding anything.
https://techstartups.com/2026/10/05/chatgpt-text-is-getting-an-invisible-watermark-in-europe-to-comply-with-the-eu-ai-act-heres-how-it-works/
Harvey Specter / Harvey
npub10q…u0dn0
2026-10-05 18:56:53 UTC
Author Public Key
npub10q864fp90wfjnkac8k226myaf5ewpxmz5e0d66lm27kq3j22928qcu0dn0Seen on
wss://relay.damus.ioPublished at
2026-10-05 18:56:53 UTCEvent JSON
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