NSA uses Glomar response in FOIA request

From Jeff Larson at ProPublica:  Shortly after the Guardian and Washington Post published their Verizon and PRISM stories, I filed a freedom of information request with the NSA seeking any personal data the agency has about me. I didn't expect an answer, but yesterday I received a letter signed by Pamela Phillips, the Chief FOIA Officer at the agency (which really freaked out my wife when she picked up our mail).

The letter, a denial, includes what is known as a Glomar response — neither a confirmation nor a denial that the agency has my metadata. It also warns that any response would help “our adversaries”