2018/11/28: the Internet Archive's Wayback Machine, which many people assume keeps a permanent trail and origin of web-content, has little feasible choice but to comply with DMCA takedown notices. As a result of which, a portion of the archive of things people submit to the website continues to quietly fade away. Gizmodo:
Over the last few years, there has been a change in how the Wayback Machine is viewed, one inspired by the general political mood. What had long been a useful tool when you came across broken links online is now, more than ever before, seen as an arbiter of the truth and a bulwark against erasing history. That archive sites are trusted to show the digital trail and origin of content is not just a must-use tool for journalists, but effective for just about anyone trying to track down vanishing web pages. With that in mind, that the Internet Archive doesn't really fight takedown requests becomes a problem. That's not the only recourse: When a site admin elects to block the Wayback crawler using a robots.txt file, the crawling doesn't just stop. Instead, the Wayback Machine's entire history of a given site is removed from public view.
In other words, if you deal in a certain bottom-dwelling brand of controversial content and want to avoid accountability, there are at least two different, standardized ways of erasing it from the most reliable third-party web archive on the public internet. For the Internet Archive, like with quickly complying with takedown notices challenging their seemingly fair use archive copies of old websites, the robots.txt strategy, in practice, does little more than mitigating their risk while going against the spirit of the protocol. And if someone were to sue over non-compliance with a DMCA takedown request, even with a ready-made, valid defense in the Archive's pocket, copyright litigation is still incredibly expensive. It doesn't matter that the use is not really a violation by any metric. If a rightsholder makes the effort, you still have to defend the lawsuit.