A month ago, the Department of Justice served a warrant (PDF) [dreamhost.com] to Dreamhost regarding one of its clients. This is routine for law enforcement to make such requests, the website hosting service said in a blog post -- except the page in question, disruptj20.org [disruptj20.org], had helped organize protests of Trump's inauguration. And the DOJ is demanding personal info and 1.3 million IP addresses of visitors to the site.
After questioning the warrant's extreme volume of info requested, the DOJ fired back with a motion (PDF) [dreamhost.com] asking the DC Superior Court to compel the host to comply. Dreamhost's counsel filed legal arguments in opposition (PDF) [dreamhost.com], and will attend a court hearing about the matter in Washington, DC on August 18th.
It's not the first time authorities have tried to pry information from internet companies on users that attended anti-Trump protests.
https://www.engadget.com/2017/08/14/doj-demands-info-1million-visitors-protest-organizing-website/ [engadget.com]
[Source]: We Fight for the Users [dreamhost.com]
[Related]: Facebook Appeal [engadget.com]