And remember: If someone is griping about your business or its products, they might have a valid complaint. Consider all complaints seriously and take corrective action when it's warranted.
Deal with Yelp, eBay, and Amazon
Third-party sites that accept reviews are some of the toughest places to protect your reputation, and that's by design. Sites such as these make it their business to protect and promote the interests of consumers, and if you're on the other side of the fence, you're automatically seen as the enemy, at least to a certain degree. Even the courts have been siding with shoppers, with recent major rulings protecting consumers' right to vent on Yelp and other consumer-review sites.
The protocol for dealing with complaints here, however, is basically the same as outlined above. Hostile and profane comments should be ignored. People who post articulate and well-conceived comments may be engaged. However, Zammuto says that Yelp can be particularly damaging. "Based on our experiences," he says, "Yelp will filter out good reviews once a brand receives bad reviews. And when the bad reviews are false and egregiously negative, Yelp will not remove them." Zammuto's approach to negative Yelp reviews is to never respond--as he says this pushes the page up on Google results--and to use SEO tactics to suppress them.
Ask for coverage
With third-party sites that allow reviews, Fertik notes that getting positive reviews is another important step in stemming the damage from negative ones. Positive reviews increase your average ratings, of course, and fresher reviews will push older reviews down the page.
"Businesses can ask customers for honest reviews to help build up the base of reviews people will see," Fertik says. "It's just important that businesses ask for accurate feedback, that they don't incentivize or pay for reviews, and that they never write fake reviews themselves."
When someone leaves a positive review, reply to it with a thank-you post, which will further increase its credibility and the perception of your responsiveness.
When a hard stance is required
If things become really nasty, you might have no choice but to get litigious. You can take any of numerous legal avenues to have negative material taken down, but generally these tactics will be successful only if some law is being broken or if defamation--something provably false said about your company--is involved.