The Web site said an herbal remedy could cure cancer and offered miraculous firsthand accounts. One woman offered to "share my experience": The formula had routed her lymphoma, sparing her radiation treatment, she said. What she didn't mention is that she also owned the company selling the product she praised online, authorities said. A growing number of regulators, trade groups and site owners are cracking down on so-called "AstroTurf" marketing - seeding the Internet with seemingly grassroots testimonials, reviews and comments that aren't as organic as they seem. The Federal Trade Commission told Holly Bacon, the owner of the herbal-remedy company, in a settlement last fall to tone down her claims and change her promotional tactics. And last month, New York Attorney General Andrew Cuomo announced a $300,000 settlement with a cosmetic-surgery firm he said had employees pose as clients to write glowing testimonials and online journals. The FTC plans to vote this summer on updating 29-year-old guidelines on endorsements, making it clear they ban phony online reviews. "While we did not have such a thing called blogs or Twitter or the social media out there in 1980, the same principles about transparency and truth in advertising apply," said Richard Cleland, assistant director of the FTC's advertising division. The European Union has responded by directing member countries to ban falsely representing oneself as a consumer, and other trade groups and businesses are deleting suspect reviews and issuing apologies. Still, some experts say it may prove difficult to enforce traditional truth-in-advertising standards on the freewheeling, ever-expanding Web. "We haven't worked out basic social and economic norms about this, much less legal norms," said Lee Rainie, director of the Pew Internet & American Life Project. "This is an environment where a lot of the rules have been scrambled." DUBIOUS TESTIMONIALS are nothing new - flip through a Victorian women's magazine. But they have found a new, global venue on the Web, with its easy anonymity and participatory, peer-to-peer ethos. Some 84 percent of Americans say online customer evaluations influence their purchases, according to an Opinion Research Corp. survey released in April. The telephone survey of 1,004 adults has a margin of sampling error of plus or minus four percentage points. Flaps over online "user" reviews go back to the 1990s. Amazon.com pulled several customer reviews of the 1999 Monica Lewinsky biography Monica's Story that had been written by a political consultant and others who hadn't read the book. In 2006, a furor erupted over a supposedly homespun blog chronicling a couple's encounters with enthusiastic Wal-Mart employees on a cross-country trip - underwritten by a group funded by Wal-Mart Stores Inc. The group's public-relations firm, Edelman, took responsibility for the blog, or "flog," in critics' terms. The prominent travel Web site TripAdvisor got attention recently for red-flagging a number of its 400,000 hotel reviews, saying it suspected they came from hoteliers seeking to pump up their ratings or knock down competitors'. Electronics maker Belkin International Inc. apologized in January after a sales staffer solicited people to write positive online reviews "as if you own the product" for a small fee; potential takers also were instructed to mark negative reviews as "not helpful." De'Longhi deleted - but defended as accurate - a dozen raves about its coffee makers on Amazon after they were exposed last month as the work of a company marketing manager, according to The Wall Street Journal's The Wallet blog. De'Longhi did not respond to inquiries from The Associated Press. Amazon's user-content chief, Russell Dicker, says the vast majority of its tens of millions of user reviews are legitimate, and the company works to sniff out fakes. The plastic-surgery firm Lifestyle Lift Inc. baldly told employees to create "postings on the Web as a satisfied client," Cuomo's office said. The company has now agreed to make sure marketing material reflects actual patients' comments and is clearly labeled as company sponsored. Cuomo said the settlement appeared to be one of the first to focus on AstroTurfing. THE FTC has said since 1980 that consumer endorsements must be honest opinions from actual customers, or clearly marked otherwise, and payments or other arrangements that would affect the testimonial's credibility must be disclosed. Proposed revisions to the guidelines emphasize that online plugs aren't exempt and say that a worker who posts a message about his company's product should "conspicuously" reveal his or her employment. The National Advertising Review Council, an industry self-regulation group, also is exploring the issue, its president, Lee Peeler, said. Some major Web retailers and consumer sites try to scrub out bogus reviews themselves. Apple makes sure reviewers in its App Store actually own the applications they critique. Consumer Reports allows only paid subscribers to post reviews on its Web site, though some comment areas are less restricted. The British consumer site Reevoo.com doesn't allow unsolicited reviews at all; instead, staffers contact buyers of various products to ask their opinions. Some site managers describe a cat-and-mouse game of ever more subtle shilling ploys and increasingly stringent responses. ILounge.com, a popular independent site about products related to Apple Inc.'s iPhone and iPod, at first simply told those offering comments its anti-AstroTurfing rules. Now two full-time employees - one a former British police officer - troll its user forums for questionable posts. The site has stopped covering some companies it branded repeat offenders and called them out publicly, despite protests that employees acted out of zeal or ignorance. "It became the only manner in which the problem could be dealt with," editor-in-chief Jeremy Horwitz said. TRADE ASSOCIATIONS in the emerging fields of online word-of-mouth marketing and "reputation management" say they're eager to stamp out tainted testimonials and are circulating ethics codes. But they acknowledge that economic pressures and the Internet's scant accountability tempt some to bend the rules. Reputation-management company ReputationDefender has been asked - and refused - to concoct both positive buzz and damaging attacks, said CEO Michael B. Fertik, who helped form his industry's Online Reputation Management Association. Such requests often come from people who say they are being unfairly maligned online and can't trace the culprit, he said. "They're feeling helpless," Fertik said. "I don't think all the people who are asking us to do fake reviews are coming from a place of malice." Bacon, the herbal-remedy company owner, genuinely believes in the healing properties of the "black salve" she sells online from Sparks, Nevada, said her lawyer, Marie C. Mirch. The FTC says the ointment and tablets may cause burns and scarring at high concentrations. Under the FTC settlement, Bacon's company, Cleansing Time Pro LLC, no longer says the salve treats cancer. The company's site still includes a testimonial - with a disclaimer noting that the writer stands to profit from a sale.