PDF Security
Auto-Lock: Make a PDF Share Link Revoke Itself the Moment Someone Tries to Copy or Screenshot It
No follow-up, no manually hitting Revoke — the link locks itself the instant it happens
5 August 2026 · 7 min read
Quick answer
Auto-lock is a per-document Guarded setting that revokes a share link the instant a copy attempt or a screenshot keyboard shortcut is detected inside the viewer — automatically, with no need for you to notice and hit Revoke yourself. It's off by default and only ever watches the share link itself, not any downloaded copy.
Real-time alerts tell you a copy or screenshot attempt happened. They don't do anything about it — you still have to notice the email, open your dashboard, and decide whether to revoke access yourself, by which point whoever tried it has had however long it took you to respond.
Auto-lock closes that gap. Turn it on for a document, and the moment a copy attempt or screenshot shortcut is detected in the viewer, the share link revokes itself — the same instant effect as you hitting Revoke, just without needing you to be watching.
What it actually watches
Auto-lock hooks into the same detection already running on every Guarded share link: a copy event firing inside the /view/[token] page, or the PrintScreen key on Windows. The first time either one fires while auto-lock is on, the document's share link is set to locked, permanently, the same one-way action as clicking Revoke from your dashboard.
Off by default, on purpose
This isn't switched on automatically for every Guarded document. It's a real, one-way access change triggered by a best-effort client-side signal — worth understanding what it can and can't detect (below) before turning it on for something where a false trigger would be genuinely disruptive, like a contract mid-negotiation with a legitimate reviewer on the other end.
Where the line actually is: the viewer page, not the PDF itself
This is the single most important limit to understand: detection only sees events reaching the viewer page's own event listeners — not interactions happening inside the PDF plugin or iframe rendering the document itself. A person selecting and copying text that pdf.js or a browser's native PDF renderer is displaying doesn't always bubble a detectable copy event up to the surrounding page. Treat every trigger as a real signal. Don't treat silence as proof nothing happened — it's inconclusive, not clean.
Screenshot detection only really works on Windows
The screenshot check listens for the PrintScreen key — a real, detectable keyboard event on Windows. On Mac, Cmd+Shift+3/4/5 never reaches this check at all: macOS intercepts that combination at the operating-system level and hands it straight to its own screenshot tool before Safari, Chrome, or any other browser's JavaScript ever sees it. That's not a gap in this feature specifically — no website on any browser can catch it on Mac.
Phone and tablet screenshots are the same story again: a hardware button combination the operating system handles directly, with zero corresponding event for any web page, anywhere, to detect. Auto-lock's screenshot check is real, but narrow — Windows only. Copy-attempt detection (Ctrl/Cmd+C) works cross-platform and is the part actually doing the work most of the time.
Link-only, exactly like everything else in Guarded
Auto-lock only ever touches the share link. It has no reach into a copy that's already been downloaded, saved, or forwarded — the same boundary that applies to burn-after-read and manual Revoke. Turning it on doesn't retroactively protect anything that already left the platform; it protects the link going forward, for people still relying on that link to view the document.
You still get the email, plus a locked link
The real-time alert email still fires when auto-lock triggers — it just now also tells you the document has already been locked, so there's nothing left for you to go do. One notification, already resolved, instead of a notification and a decision.
A permanent record shows up in your dashboard too
Every copy or screenshot attempt — whether or not auto-lock is on — is logged with its event type, country, and exact timestamp on your analytics dashboard, not just sent once by email and then gone. Useful on its own even without auto-lock turned on, as a persistent record of what was attempted and when.
How to turn it on
Auto-lock is available two ways: turn on Guarded for any document on any tool page and tick "Auto-lock on copy or screenshot attempt" in the Pro security options before you create it, or turn it on afterward, per document, from the toggle next to each document on your analytics dashboard. Either way, it's off until you explicitly turn it on.
Where auto-lock earns its place
A few situations where an instant, unattended lock is worth more than an alert you might not see for an hour:
- A document you can't monitor closely — sent right before you're offline for a while
- Something genuinely single-use, where any attempt at all is reason enough to shut the link down
- A highly sensitive disclosure where the cost of a delayed manual revoke outweighs the (small) risk of a false trigger
Frequently asked questions
Does auto-lock affect a copy that's already been downloaded?
No. It only revokes the share link. A copy that already left the platform — downloaded, forwarded, or emailed — is unaffected either way.
Can auto-lock be turned back off once it's locked a document?
No — locking is one-way, whether it comes from auto-lock, burn-after-read, or clicking Revoke yourself. Send a fresh link if access is needed again.
Will auto-lock catch someone taking a photo of their screen with another device?
No. That happens entirely outside the browser and leaves no event for any website to detect, with or without auto-lock.
Does turning on auto-lock replace real-time alerts?
No — they run together. The alert email still fires; it now also tells you the link has already been locked, so you're informed rather than expected to act.
Can I turn on auto-lock at the same time as beacon or photo verification?
Yes — all of Guarded's options are independent toggles on the same document and are commonly combined.
Is auto-lock a free feature?
It's part of Guarded, iGuardPDF's Pro tier — see pricing for the full comparison.
Related tools
Auto-lock is one layer of Guarded — most people pair it with:
An alert tells you something happened. Auto-lock does something about it, the instant it happens, without waiting on you to be at your desk. It won't catch everything — nothing watching from inside a browser tab ever fully can — but for the things it does catch, the response is immediate instead of however long it takes you to check your email.
Ready to make your share links defend themselves?
Auto-lock is built into Guarded — turn it on for any document you share.
See Pro plans →Safe in our hands
iGuardPDF takes file handling seriously. A few things worth knowing, whichever tool you're using:
- Every upload and download runs over TLS (HTTPS) — your file never crosses the network unencrypted.
- Files are processed to run the tool you asked for, then deleted. We don't archive uploads or keep a copy afterward.
- Free tools need no account, so there's no identity to build a tracking profile against in the first place.
- Nothing you upload is ever used to train an AI model, ours or anyone else's.
Full breakdown on our Security page.