Libgen, the largest online repository of free books and academic articles, has pretty much vanished from the Internet. Earlier this month the site's operators were sued by academic publishing company Elsevier, who asked a New York federal court for a preliminary injunction hoping to keep the site down for good.

Most of the top academic articles are published in journals that can only be accessed legally through expensive paywalls.

The Library Genesis Project, or Libgen for short, has systematically breached this barrier by hosting pirated copies of scientific publications as well as mainstream books.

Earlier this month one of the largest publishers went into action to stop this threat. Elsevier filed a complaint at a New York District Court, hoping to shut down Libgen.org and several sister sites.

The case has barely got going but the main Libgen.org site as well as several of its mirrors have been offline for the past few days.

The downtime is not the result of the preliminary injunction Elsevier requested, as that hasn’t been granted yet. However, a few days ago the court did approve the publishers’ motion to serve Libgen’s operators via email.

In addition, a recent court filing shows that Elsevier’s lawyers have taken action on their own. They contacted the Public Interest Registry (.ORG) hoping to disable an infringing domain name without interference of the court.

The .ORG registry refused to do so, noting that it would require a valid court order to suspend a domain name.

“Through its counsel, the Public Interest Registry informed me that it does not disable domains absent a valid court order, but would promptly comply with a valid court order to disable a domain,” Elsevier’s lawyer informs the court.

Whether Libgen’s downtime is a direct result of Elsevier’s interference is unknown at this point, but the .org domain as well as the popular .in alternative are currently unreachable due to nameserver issues.

There are some other ‘mirrors’ that still work though, including Libgen.biz and Gen.lib.rus.ec. The .biz domain points to the same IP-address range the official domain used, suggesting that Libgen’s hosting servers are still operational.

Several other domains named in the lawsuit, including bookfi.org and sci-hub.org, also remain online.

In a few weeks the New York federal court will decide whether to issue the preliminary injunction or not. Until then, Libgen’s operators have the option to oppose the request.

If the injunction is granted it will be much harder for Libgen to operate. Among other things, it would allow Elsevier to order hosting companies, domain name registries and search engines to stop providing services to the site.