But the anonymity that has emboldened countless Internet users to post their opinions on everything from stocks to religious cults is increasingly being punctured by a simple legal maneuver.
Publicly traded companies and other targets of such postings are filing a surging number of "John Doe" lawsuits that enable them to subpoena the identities of their online critics from America Online, Yahoo and other Internet firms.
The trend underscores the difficulties of striking a balance between anonymity and accountability on the Internet, a medium on which millions of people--rightly or wrongly--have come to expect the ability to communicate anonymously with others.
Companies that file the "John Doe" suits say the tactic is one of their few weapons against what they consider digital defamation. It seems to be working, often forcing online critics to slink away from message boards and in some cases exposing critics within the companies themselves who subsequently leave or are fired.
But the growing volume of these suits--and the subsequent dropping of them in some cases after identities have been disclosed--makes some experts fear that the legal process is being abused by organizations seeking only to "out" online foes.
"What we're seeing is an all-out assault on anonymity on the Internet," said David Sobel, general counsel at the Electronic Privacy Information Center. "No one assesses the validity of these suits before the identities are disclosed."
Dozens of "John Doe" suits--so named because they are filed before the real name of the defendant is known--have been filed across the country in recent months, including a flurry of them in Southern California. In one of these cases, a "John Doe" defendant is fighting back for the first time.
Today in Ventura County, attorneys representing a man with the Internet handle "A View From Within" are scheduled to appear in Superior Court to fight an attempt to unmask him by Xircom Inc., a Thousand Oaks-based computer modem maker.
The use of the legal tactic is also spreading beyond the corporate world. A law firm affiliated with the Church of Scientology, for example, last week compelled AT&T's Internet service to reveal the name of a subscriber who had been critical of the church in an online newsgroup.
"It is terrifyingly easy to rip off the cover of anonymity," said Daniel Leipold, a Santa Ana attorney who represents the man. "If Thomas Paine [the anonymous pamphleteer who helped spark the American Revolution] had ever been subject to these John Doe suits, the British would have hung him."
Of course, few of the defendants in these cases are the literary equals of Paine. Many cases center on the anonymous postings of people hiding behind such monikers as "JPMoron" and "Eye M Rude."
Typically, the cases involve postings to message boards that are designed as discussion forums for investors. America Online, Yahoo and others have erected thousands of such boards, covering virtually every publicly traded company.
The boards are as unruly as they are popular, and messages range from thoughtful comments to profane rants to potentially libelous allegations. Cohr Inc. in Chatsworth, for instance, recently charged a former executive with being behind messages that accused current company officials of sexual misconduct, among other things.
But there are concerns that more recent cases threaten the Internet as a platform for free speech. A particularly troubling example, free speech advocates say, came recently when Raytheon Co., a Massachusetts-based defense firm, filed a John Doelawsuit and subpoenaed the names of 21 individuals who had made postings to a Raytheon message board operated by Yahoo.
Yahoo asks users for their names and valid e-mail addresses before allowing them to post to message boards. After Raytheon collected the 21 names, which included a number of company employees, the suit was dropped. Four of the identified employees have since left the company.
"Our motive behind this suit had nothing to do with curbing free speech," said David Polk, a spokesman for Raytheon. "We did what was necessary to keep proprietary information from being disclosed in an unauthorized way. We felt it was time to put the matter behind us."
But to others, the quick dropping of the suit was a sign that "in this environment, discovery procedures are subject to abuse," Sobel said.
The issue highlights the difficulties presented by the Internet's emergence as a mainstream, and largely anonymous, medium. Chat rooms, message boards and newsgroups are populated by millions of nameless contributors, people who might have shuddered at the thought of receiving an anonymous phone call or letter.
Before the Net, companies had a great deal more control over the dissemination of information about them. But now everyday people can broadcast opinions to a large audience with minimal effort. That may lead to abuses, experts say, but it also empowers critics, investors and corporate whistle blowers. In the face of these changes, John Doe suits are particularly effective because they give companies the legal authority to subpoena information that might be relevant to the case.
According to UCLA law professor Jerry Kang, the courts give plaintiffs broad latitude to dig up such information, and that attempts to quash subpoenas are difficult to win. "Most judges do not like resolving discovery disputes," he said. "They think it's like children fighting."
Federal law does nothing to prevent Internet companies from disclosing the identities of their subscribers and users to anyone who asks. But most Internet firms have voluntarily adopted policies by which they release such information only when faced with a subpoena, court order or warrant.
Some companies, including America Online, notify subscribers that their information has been subpoenaed, and give them 14 days to respond. But others, including Yahoo, comply without warning users.
As a result, many defendants in John Doe suits are unmasked before they are aware they have been targeted. The defendant in the Xircom case, for instance, found out about the suit only because it was reported in the press.
The postings of "A View From Within"--his Yahoo moniker--are tame by message board standards, calling executives "jokers" and saying the sales director is "more concerned with finding his lost hair gel than he is about sales growth."
But he also portrayed himself as an engineer at the company--a claim his attorney says is false--and warned investors that Xircom was trying to conceal defects in some of its products. Xircom's suit, filed last month, accuses him of defamation and seeks at least $25,000 in damages.
Hoping to maintain his anonymity, the man has filed a motion to quash the subpoena for his information from Yahoo. In the motion, his attorney argues that the subpoena is flawed on procedural grounds, but also that it threatens protections the Supreme Court has erected around anonymous speech.
Xircom has pledged to fight the motion to quash the subpoena, and to forge ahead with the suit. Internet firms are becoming frequent targets of legal probes in other legal settings as well. Increasingly, Internet firms are being subpoenaed for electronic records in divorce proceedings and are being asked to furnish information in criminal investigations. America Online has been served with more than 110 warrants so far this year in investigations involving its members.
Bridge Publications Inc., which publishes literature for the Church of Scientology, recently took advantage of a federal law enacted last year--the Digital Millennium Copyright Act--that allows subpoenas to be issued even without the filing of a suit in cases involving potential copyright infringement.