Yahoo searched hundred of millions of incoming emails for the federal government in 2015, the Associated Press reports.
Citing three former Yahoo employees, the report states that the NSA or FBI demanded that the internet company search for a string of letters, numbers or other characters.
To conduct the surveillance, Yahoo built a software program.
Google said Tuesday that it has not received similar surveillance demands, and if it did, the response would be, “No way.” Microsoft said it has “never engaged in secret scanning of email traffic.”
Twitter and Facebook also responded that they have not received similar requests.