Reverse search warrant

A reverse search warrant is a type of search warrant used in the United States, in which law enforcement obtains a court order for information from technology companies to identify a group of people who may be suspects in a crime. They differ from traditional search warrants, which typically apply to specific individuals.^[1][2] Geo-fence warrants, which seek data on mobile phone users who were in a specific location at a given time, and keyword warrants, which request information on users who searched specific phrases, are two types of reverse search warrants.^[2]