Jonathan Zittrain:

Some colleagues and I joined those investigating the extent of link rot in 2014 and again this past spring.

The first study, with Kendra Albert and Larry Lessig, focused on documents meant to endure indefinitely: links within scholarly papers, as found in the Harvard Law Review; and judicial opinions of the Supreme Court. We found that 50 percent of the links embedded in Court opinions since 1996, when the first hyperlink was used, no longer worked. And 75 percent of the links in the Harvard Law Review no longer worked.

People tend to overlook the decay of the modern web, when in fact these numbers are extraordinary — they represent a comprehensive breakdown in the chain of custody for facts. Libraries exist, and they still have books in them, but they aren’t stewarding a huge percentage of the information that people are linking to, including within formal, legal documents. No one is. The flexibility of the web — the very feature that makes it work, that had it eclipse CompuServe and other centrally organized networks — diffuses responsibility for this core societal function. 

A very interesting article — I’m saving it as a PDF because who knows what may happen to the link? (Maybe I should print it out as well….)