The U.S. Federal Bureau of Investigation has withdrawn a secret demand that the Internet Archive, an online library, provide the agency with a user's personal information after the Web site challenged the records request in court.

The FBI sent a national security letter, or NSL, to the Internet Archive in November and included a gag order barring site founder Brewster Kahle from talking to anyone other than his lawyers about the request. Kahle, the Electronic Frontier Foundation (EFF) and the American Civil Liberties Union (ACLU) filed a lawsuit to challenge the subpoena, arguing that the NSL program is unconstitutional, and the FBI withdrew the NSL on April 22.

The settlement between the FBI and the Internet Archive allowed Kahle to break the gag order, a standard part of an NSL request. The Internet Archive's challenge of the NSL is only the third case that the ACLU is aware of in which an NSL has been challenged in court, said Melissa Goodman an attorney for the civil liberties group's National Security Project.

"The NSLs basically allow the FBI to demand extremely sensitive personal information about innocent people without any prior court approval, often in total secrecy," Goodman said Wednesday.

The NSL program, expanded when Congress passed the antiterrorism Patriot Act shortly after the Sept. 11, 2001, attacks on the U.S., allows the FBI and other U.S. government agencies to issue administrative subpoenas to U.S. businesses for customer and other personal information.

FBI Assistant Director John Miller issued a statement about the case Wednesday. "The information requested in the national security letter was relevant to an ongoing, authorized national security investigation," he said. "National security letters remain indispensable tools for national security investigations and permit the FBI to gather the basic building blocks for our counterterrorism and counterintelligence investigations."

Although the settlement keeps parts of the FBI request secret, Kahle applauded the lawsuit and settlement, saying it will show other businesses how to challenge NSLs. The FBI issued nearly 200,000 NSLs between 2003 and 2006, according to a U.S. Department of Justice inspector general's report.

"We see this as an unqualified success," Kahle said during a news conference. "The goal here was to help other recipients of NSLs ... understand that you can push back on these."

The gag order prevented Kahle from discussing the case with the library's board of directors, staff, and even his wife, he said. "Gags don't seem to be necessary," he said. "Gagging librarians is horrendous."

Kahle's lawyers declined to talk about the nature of the FBI investigation or reveal the identity of the targeted user.

The NSL sent to the Internet Archive asked for a user's name, address, length of service, e-mail header information and activity logs. The FBI investigation was "relevant to an authorized investigation to protect against international terrorism or clandestine intelligence activities," according to the FBI letter.

The Internet Archive provided the FBI some information that was publicly available on the site, but could not comply with the FBI request because the site does not track user activity or record IP (Internet Protocol) addresses, said Kurt Opsahl, a senior staff attorney with the EFF. The site asks only for an unverified e-mail address when users register.

Opsahl responded to the NSL in December. In addition to telling the FBI that the Internet Archive does not collect most of the personal information it sought, Opsahl also told the agency the Internet Archive was challenging the NSL on constitutional grounds. The U.S. District Court for the Southern District of New York found the NSL program unconstitutional in September 2004, with the gag orders a violation of the First Amendment rights to free speech, Opsahl noted. The judge in the case has delayed his order pending government appeal.

Congress also gave some protections from NSLs to libraries in 2006, Opsahl told the FBI.

In each of the three court challenges to the NSL program, the FBI has withdrawn the information demands, ACLU's Goodman said. "I think that calls into question how much the FBI needed the information in the first place and, frankly, whether the FBI needs this kind of sweeping and unchecked surveillance power," she said.