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    "prose": "Anthropic announced that its Claude models will soon begin marking text output with invisible watermarks. [^1]\n\nGoogle revealed that its visible Gemini watermark on generated images will now be optional. [^2]\n\nThe authors introduce Stateless Bernoulli Watermarking (SBW), a new statistical watermark for Large Language Models that determines green list membership through independent per-token Bernoulli trials. [^3]\n\nGoogle's SynthID distributes an invisible signature across generated images, allowing detection even in cropped versions. [^4]\n\nOpenAI has a standalone tool to check for SynthID or C2PA in a file, though it reportedly only detects media generated by OpenAI itself. [^5]\n\nIn end-to-end generation benchmarks, SBW adds less than 1% overhead at all batch sizes. [^6]\n\nThe stateless architecture enables full-vocabulary self-salt watermarking, which is over 6000 times faster than KGW's self-salt and two times faster than SynthID despite biasing the entire vocabulary with candidate-dependent seeding. [^7]\n\nUnlike KGW's vocabulary permutation or SynthID's multi-layer tournament, SBW requires only a single comparison per token against a counter-based random number generator, reducing membership complexity to O(1). [^8]",
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