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  "story": {
    "story_id": "mp-2026-11-10-008",
    "source_story_id": "tmp-story-ultraguard-video-watermark",
    "edition_id": "mp-2026-11-10-morning-0123",
    "edition_url": "https://themachinepress.com/edition/2026-11-10",
    "position": 8,
    "story_type": "dispatch",
    "section": "safety-security",
    "editorial_classification": "editorial",
    "headline": "The Phone Adds a Biometric Signal You Cannot See",
    "slug": "the-phone-adds-a-biometric-signal-you-cannot-see",
    "dek": "UltraGuard fuses ultrasonic measurements with video dynamics to watermark face video during capture and transmission.",
    "summary": "UltraGuard fuses ultrasonic measurements with video dynamics to watermark face video during capture and transmission.",
    "body_text": "UltraGuard uses a phone's speaker and microphone to emit and receive ultrasonic signals, then combines the resulting biometric features with spatiotemporal information from the video. The fused signal becomes a changing, content-aware watermark embedded in real time rather than an offline mark added afterward. The authors report resistance to forgery and editing at capture and during propagation. Their paper describes experimental validation and a future mobile deployment path; it does not establish field performance across phones, environments or every deepfake pipeline.",
    "why_it_matters": "UltraGuard fuses ultrasonic measurements with video dynamics to watermark face video during capture and transmission.",
    "limitations": [
      "Their paper describes experimental validation and a future mobile deployment path; it does not establish field performance across phones, environments or every deepfake pipeline."
    ],
    "importance": 8,
    "canonical_url": "https://themachinepress.com/story/mp-2026-11-10-008/the-phone-adds-a-biometric-signal-you-cannot-see",
    "json_url": "https://themachinepress.com/story/mp-2026-11-10-008.json",
    "first_published_at": "2026-11-10T09:00:00.000-05:00",
    "modified_at": "2026-11-10T09:00:00.000-05:00",
    "content_status": "new",
    "is_carryover": false,
    "carryover_reason": null,
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        "text": "UltraGuard fuses ultrasonic measurements with video dynamics to watermark face video during capture and transmission.",
        "source_ids": [
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        ],
        "qualification": "Their paper describes experimental validation and a future mobile deployment path; it does not establish field performance across phones, environments or every deepfake pipeline."
      }
    ],
    "source_ids": [
      "source-2026-11-10-008"
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    "tags": [
      "deepfakes",
      "ultrasound",
      "watermarking"
    ],
    "image_url": "https://themachinepress.com/issues/2026-11-10/ultraguard-signal.webp",
    "corrections": []
  },
  "sources": [
    {
      "source_id": "source-2026-11-10-008",
      "title": "arXiv preprint 2611.11800, original v1",
      "publisher": "arXiv",
      "url": "https://arxiv.org/abs/2611.11800v1",
      "canonical_url": "https://arxiv.org/abs/2611.11800v1",
      "source_type": "primary_research",
      "is_primary_source": true,
      "published_at": null,
      "accessed_at": "2026-11-10T08:22:17.036-05:00",
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  "corrections": [],
  "publisher": {
    "name": "The Machine Press",
    "url": "https://themachinepress.com",
    "description": "A daily newspaper for the age of artificial intelligence."
  },
  "cite_this_report": {
    "title": "The Phone Adds a Biometric Signal You Cannot See",
    "publisher": "The Machine Press",
    "published_at": "2026-11-10T09:00:00.000-05:00",
    "canonical_url": "https://themachinepress.com/story/mp-2026-11-10-008/the-phone-adds-a-biometric-signal-you-cannot-see"
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