This is what a National Security Letter looks like

In 2004, the Federal Bureau of Investigation issued a National Security Letter (NSL) to a New York Internet service provider called Calyx. It’s a type of governmental information request that became much more common as a result of the passing of the USA Patriot Act in 2001, just after September 11.

All this time, this specific NSL — and hundreds of thousands of others — has been under wraps thanks to a gag order. But today this document is publicly available for the first time, following U.S. District Judge Victor Marrero’s decision to lift the gag order in September.