DreamHost had argued the DoJ's warrant would have revealed 1.3 million IP addresses.
The DoJ has now narrowed the scope of its demand.
Disruptj20.org was set up to help arrange a protest at President Trump's inauguration.
"The government has no interest in records relating to the 1.3 million IP addresses that are mentioned in DreamHost's numerous press releases and opposition briefs," prosecutors said in the new request.
They were focused on the use of the website to plan and carry out a criminal act - a "riot" - not the "lawful activities of peaceful protesters", they said.
The warrant does not now require certain access and error logs, which, DreamHost says, means visitors' IP addresses are "largely safe".
"We see this as a huge win for internet privacy, and we absolutely appreciate the DoJ's willingness to look at and reconsider both the scope and the depth of their original request for records," DreamHost said in a blog post.
However, it still plans to challenge the DoJ on other aspects of its request.
Prosecutors signed the original warrant to DreamHost in July, arguing that disruptj20.org had been used to organise "violent" protests in Washington DC.
DreamHost and privacy advocates argued that amounted to a "digital dragnet".
In its updated warrant, the DoJ said that the full scope of the original request - criticised by DreamHost in its public statements - had been "unknown to the government and the court at the time that the warrant was issued".
Data still required by the amended warrant includes files and databases stored by DreamHost.
More than 200 people have been charged in relation to rioting at the inauguration.
Visitors to an anti-Trump website will probably not have their internet protocol addresses turned over to the Department of Justice, after a legal standoff with a US web company.