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    "section": "safety-security",
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    "headline": "One Watermark Survived; the Other Broke",
    "slug": "one-watermark-survived-the-other-broke",
    "dek": "A robust signal tracked provenance while a fragile companion signaled reader-visible tampering.",
    "summary": "A robust signal tracked provenance while a fragile companion signaled reader-visible tampering.",
    "body_text": "Independent keys and seeding windows produced three detector outcomes: intact, tampered or unwatermarked. Tests on two models and two prompt datasets reported the strongest tamper detection among compared methods while preserving competitive attribution robustness.",
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    "modified_at": "2026-08-16T15:43:36.912-04:00",
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    "tags": [
      "watermarking",
      "tamper detection",
      "provenance"
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    "image_url": null,
    "corrections": []
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  "sources": [
    {
      "source_id": "source-2026-08-16-019",
      "title": "arXiv preprint 2608.12713",
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      "published_at": "2026-08-12T21:55:16.000-04:00",
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    "name": "The Machine Press",
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    "description": "A daily newspaper for the age of artificial intelligence."
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  "cite_this_report": {
    "title": "One Watermark Survived; the Other Broke",
    "publisher": "The Machine Press",
    "published_at": "2026-08-16T09:00:00.000-04:00",
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