Twitter on Friday released two national security letters it received from the FBI in the last two years that previously came with gag orders not to discuss them.
In a blog post, the social network said it had been ordered by the feds to provide the name, address and other pertinent information of a user account in 2015, and another in 2016, and to not notify the users.
In the released letters, the account names and the names of the specific investigating agencies were redacted.
Twitter's action comes several weeks after tech companies including Google, Yahoo and Cloudflare published national security letters received from the FBI, some dating back to 2013.
"Twitter remains unsatisfied with restrictions on our right to speak more freely about national security requests we may receive," wrote Elizabeth Banker, Twitter's associate general counsel. "We would like a meaningful opportunity to challenge government restrictions when 'classification' prevents speech on issues of public importance."
Twitter sued the Justice Department in 2014 to lift any gag orders placed on the company regarding national security inquiries involving its users. Twitter said it was prohibited from disclosing how many letters it had received.
The parties are due back in court next month.
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