# ByteMark

Detecting a watermark in large-model text used to require the generating side's tokenizer or semantic embedding pipeline, which the text itself does not reveal, so text of unknown origin was hard to verify. ByteMark defines its signal on the UTF-8 byte stream of the published text; participating models embed it under one public specification and key, and a verifier needs only the text and the key. In experiments, replacing the detector's tokenizer or embedding model sharply degraded token-level and sentence-level baselines, while ByteMark's detection rate was unchanged, and it stayed detectable through a relay of models and after participating rewriters re-embedded the watermark.

Detecting a watermark in large-model text used to require the generating side's tokenizer or semantic embedding pipeline, which the text itself does not reveal, so text of unknown origin was hard to verify. ByteMark defines its signal on the UTF-8 byte stream of the published text; participating models embed it under one public specification and key, and a verifier needs only the text and the key. In experiments, replacing the detector's tokenizer or embedding model sharply degraded token-level and sentence-level baselines, while ByteMark's detection rate was unchanged, and it stayed detectable through a relay of models and after participating rewriters re-embedded the watermark.