{
  "schema": "https://storagestudio.us/schema/wiki-page.v1",
  "title": "File ownership on external drives",
  "slug": "file-ownership-on-external-drives",
  "url": "https://storagestudio.us/wiki/file-ownership-on-external-drives",
  "markdown_url": "https://storagestudio.us/wiki/file-ownership-on-external-drives.md",
  "category": "External drives",
  "category_url": "https://storagestudio.us/wiki/external-drives/",
  "tags": [
    "external drive",
    "glossary",
    "data parking"
  ],
  "summary": "Every file on your Mac belongs to a user account, but macOS usually ignores ownership on external drives. That's why moved files show you as their owner, and why Storage Studio's moves don't keep ownership — while they do keep permissions, dates and the rest.",
  "published_at": "2026-10-01T06:15:48.000Z",
  "updated_at": "2026-10-01T05:34:30.000Z",
  "headings": [
    {
      "level": 2,
      "text": "macOS ignores ownership on most external drives",
      "id": "macos-ignores-ownership-on-most-external-drives"
    },
    {
      "level": 2,
      "text": "What this means for your moves",
      "id": "what-this-means-for-your-moves"
    },
    {
      "level": 2,
      "text": "When you might notice",
      "id": "when-you-might-notice"
    }
  ],
  "links_out": [
    {
      "slug": "what-a-move-keeps",
      "label": "What a move keeps",
      "exists": true,
      "url": "https://storagestudio.us/wiki/what-a-move-keeps"
    },
    {
      "slug": "why-some-apps-cant-be-moved",
      "label": "Why some apps can't be moved",
      "exists": true,
      "url": "https://storagestudio.us/wiki/why-some-apps-cant-be-moved"
    },
    {
      "slug": "glossary-file-ownership",
      "label": "File ownership",
      "exists": true,
      "url": "https://storagestudio.us/wiki/glossary-file-ownership"
    },
    {
      "slug": "exfat-drives",
      "label": "What to know about exFAT drives",
      "exists": true,
      "url": "https://storagestudio.us/wiki/exfat-drives"
    },
    {
      "slug": "drive-formats",
      "label": "Drive formats",
      "exists": true,
      "url": "https://storagestudio.us/wiki/drive-formats"
    }
  ],
  "links_in": [
    {
      "slug": "glossary-file-ownership",
      "title": "File ownership",
      "url": "https://storagestudio.us/wiki/glossary-file-ownership"
    },
    {
      "slug": "what-a-move-keeps",
      "title": "What a move keeps",
      "url": "https://storagestudio.us/wiki/what-a-move-keeps"
    },
    {
      "slug": "exfat-drives",
      "title": "What to know about exFAT drives",
      "url": "https://storagestudio.us/wiki/exfat-drives"
    }
  ],
  "diagrams": [
    {
      "kind": "flowchart",
      "caption": "What happens to a file's owner on a trip to the drive and back",
      "outline": "- File on your Mac - owned by you\n  - leads to On the drive - shown as owned by whoever is using the Mac\n- On the drive - shown as owned by whoever is using the Mac\n  - leads to Moved back - owned by you again\n",
      "source": "%% caption: What happens to a file's owner on a trip to the drive and back\nflowchart LR\n  A[File on your Mac - owned by you] --> B[On the drive - shown as owned by whoever is using the Mac]\n  B --> C[Moved back - owned by you again]"
    }
  ],
  "images": [],
  "screenshots_pending": [],
  "faqs": [
    {
      "question": "How do I move apps to an external drive on a Mac and still launch them?",
      "answer": "Dragging an app to another drive can break it, because macOS expects it in /Applications. Storage Studio relocates the app to your external drive and leaves a shortcut in place, so it still launches normally from Launchpad, Spotlight, and the Dock — and you can move it back in one click.",
      "url": "https://storagestudio.us/faq"
    },
    {
      "question": "How do I use an external SSD as extra storage on a MacBook?",
      "answer": "Plug in a USB-C or Thunderbolt SSD and let Storage Studio pair it with your internal drive as one workspace. It moves big folders, libraries, and apps to the SSD with a shortcut left behind, so your MacBook behaves like it has a much bigger disk — fast enough to work directly off the external drive.",
      "url": "https://storagestudio.us/faq"
    },
    {
      "question": "Can I move my Photos or Final Cut library to an external drive?",
      "answer": "Yes — large Photos, Final Cut, and iMovie libraries are common space hogs. Storage Studio relocates them to an external drive while keeping them usable, leaving a shortcut so your apps still find them. Moving a folder to your fast drive keeps its files' modified and created dates, permissions,…",
      "url": "https://storagestudio.us/faq"
    },
    {
      "question": "Will moving files to another drive break my apps or Spotlight?",
      "answer": "Not the way Storage Studio does it. It leaves a shortcut (symlink) at the original location, so apps, Finder, and Spotlight resolve everything as if it never moved — and the move is fully reversible.",
      "url": "https://storagestudio.us/faq"
    }
  ],
  "text": "On your Mac's built-in disk, every file has an owner — the user account it belongs to — and permissions that say what the owner and everyone else may do with it. External drives work a little differently, and that affects what a move can keep. macOS ignores ownership on most external drives When you connect an external drive, macOS usually treats it as a drive you might plug into any Mac. On such a drive, the account numbers that record ownership on one Mac would mean nothing on another, so macOS sets the drive to ignore ownership . You can see this in Finder: select the drive, choose Get Info , and look for the Ignore ownership on this volume checkbox under Sharing & Permissions . With ownership ignored: every file on the drive appears to belong to whoever is using the Mac at the time; setting a file's owner on the drive has no lasting effect. On an APFS or Mac OS Extended drive, the files' permissions — read, write and run — are still stored. What this means for your moves Storage Studio's folder moves keep each file's permissions, dates, Finder tags and much more — see What a move keeps . They don't keep ownership , for two reasons: On a drive that ignores ownership, there's nothing to keep it in. Storage Studio moves your files as you, not as an administrator, so it can't make a file belong to a different account. What happens to a file's owner on a trip to the drive and back Flowchart outline: What happens to a file's owner on a trip to the drive and back File on your Mac - owned by you leads to On the drive - shown as owned by whoever is using the Mac On the drive - shown as owned by whoever is using the Mac leads to Moved back - owned by you again For almost everyone this changes nothing you'd notice. The folders you move are your own, and when they come back to your Mac they belong to you, just as before. When you might notice On a shared Mac. If you move a folder that belongs to another person's account, it comes back belonging to you. Move only your own folders, or have each person move their own. Apps installed for the whole Mac. Some apps belong to the system account rather than to a person. The Apps window doesn't offer to move those — see Why some apps can't be moved . See also: File ownership , What to know about exFAT drives , Drive formats . Common questions How do I move apps to an external drive on a Mac and still launch them? Dragging an app to another drive can break it, because macOS expects it in /Applications. Storage Studio relocates the app to your external drive and leaves a shortcut in place, so it still launches normally from Launchpad, Spotlight, and the Dock — and you can move it back in one click. How do I use an external SSD as extra storage on a MacBook? Plug in a USB-C or Thunderbolt SSD and let Storage Studio pair it with your internal drive as one workspace. It moves big folders, libraries, and apps to the SSD with a shortcut left behind, so your MacBook behaves like it has a much bigger disk — fast enough to work directly off the external drive. Can I move my Photos or Final Cut library to an external drive? Yes — large Photos, Final Cut, and iMovie libraries are common space hogs. Storage Studio relocates them to an external drive while keeping them usable, leaving a shortcut so your apps still find them. Moving a folder to your fast drive keeps its files' modified and created dates, permissions,… Will moving files to another drive break my apps or Spotlight? Not the way Storage Studio does it. It leaves a shortcut (symlink) at the original location, so apps, Finder, and Spotlight resolve everything as if it never moved — and the move is fully reversible.",
  "markdown": "On your Mac's built-in disk, every file has an **owner** — the user account it belongs to — and permissions that say what the owner and everyone else may do with it. External drives work a little differently, and that affects what a move can keep.\n\n## macOS ignores ownership on most external drives\n\nWhen you connect an external drive, macOS usually treats it as a drive you might plug into any Mac. On such a drive, the account numbers that record ownership on one Mac would mean nothing on another, so macOS sets the drive to **ignore ownership**. You can see this in Finder: select the drive, choose **Get Info**, and look for the **Ignore ownership on this volume** checkbox under **Sharing & Permissions**.\n\nWith ownership ignored:\n\n- every file on the drive appears to belong to whoever is using the Mac at the time;\n- setting a file's owner on the drive has no lasting effect.\n\nOn an APFS or Mac OS Extended drive, the files' **permissions** — read, write and run — are still stored.\n\n## What this means for your moves\n\nStorage Studio's folder moves keep each file's permissions, dates, Finder tags and much more — see [What a move keeps](https://storagestudio.us/wiki/what-a-move-keeps). They don't keep **ownership**, for two reasons:\n\n1. On a drive that ignores ownership, there's nothing to keep it in.\n2. Storage Studio moves your files as you, not as an administrator, so it can't make a file belong to a different account.\n\n```mermaid\n%% caption: What happens to a file's owner on a trip to the drive and back\nflowchart LR\n  A[File on your Mac - owned by you] --> B[On the drive - shown as owned by whoever is using the Mac]\n  B --> C[Moved back - owned by you again]\n```\n\n*Flowchart — What happens to a file's owner on a trip to the drive and back. Outline:*\n\n- File on your Mac - owned by you\n  - leads to On the drive - shown as owned by whoever is using the Mac\n- On the drive - shown as owned by whoever is using the Mac\n  - leads to Moved back - owned by you again\n\nFor almost everyone this changes nothing you'd notice. The folders you move are your own, and when they come back to your Mac they belong to you, just as before.\n\n## When you might notice\n\n- **On a shared Mac.** If you move a folder that belongs to another person's account, it comes back belonging to you. Move only your own folders, or have each person move their own.\n- **Apps installed for the whole Mac.** Some apps belong to the system account rather than to a person. The Apps window doesn't offer to move those — see [Why some apps can't be moved](https://storagestudio.us/wiki/why-some-apps-cant-be-moved).\n\nSee also: [File ownership](https://storagestudio.us/wiki/glossary-file-ownership), [What to know about exFAT drives](https://storagestudio.us/wiki/exfat-drives), [Drive formats](https://storagestudio.us/wiki/drive-formats).\n\n- **How do I move apps to an external drive on a Mac and still launch them?** Dragging an app to another drive can break it, because macOS expects it in /Applications. Storage Studio relocates the app to your external drive and leaves a shortcut in place, so it still launches normally from Launchpad, Spotlight, and the Dock — and you can move it back in one click. (https://storagestudio.us/faq)\n- **How do I use an external SSD as extra storage on a MacBook?** Plug in a USB-C or Thunderbolt SSD and let Storage Studio pair it with your internal drive as one workspace. It moves big folders, libraries, and apps to the SSD with a shortcut left behind, so your MacBook behaves like it has a much bigger disk — fast enough to work directly off the external drive. (https://storagestudio.us/faq)\n- **Can I move my Photos or Final Cut library to an external drive?** Yes — large Photos, Final Cut, and iMovie libraries are common space hogs. Storage Studio relocates them to an external drive while keeping them usable, leaving a shortcut so your apps still find them. Moving a folder to your fast drive keeps its files' modified and created dates, permissions,… (https://storagestudio.us/faq)\n- **Will moving files to another drive break my apps or Spotlight?** Not the way Storage Studio does it. It leaves a shortcut (symlink) at the original location, so apps, Finder, and Spotlight resolve everything as if it never moved — and the move is fully reversible. (https://storagestudio.us/faq)\n"
}