"Yelp treats review content equally for advertisers and non advertisers alike. And advertisers pay for advertising, not control over reviews on their page," he said. "This credibility of review content is critical to Yelp's value and is precisely why 29 million people used the site last month to find a great local business."
Though he said that the recency of a review, the credibility of a reviewer and the Yelp community's response to a review can affect its ranking on a business's page, he said he couldn't elaborate on the algorithm the company uses to rank reviews.
"We see daily attempts to write fake reviews promoting one business or negative reviews attacking a competitor," he said. "In order to protect consumers and businesses alike from being victimized by fake or malicious reviews, we employ an automated algorithm that we can't disclose entirely or else people will game the system."
Though some businesses may wonder why reviews disappear or move around a page, he said the algorithm that drives the rankings is set up to be dynamic and devoid of human bias.
Even before these recent lawsuits, Yelp has faced extortion accusations.
A story published last year by East Bay Express in Oakland, Calif., featured a number of area business owners who said Yelp offered to bury negative reviews if they signed up for a monthly ad subscription.
At the time, the company's COO Geoff Donaker said it wasn't within advertisers' and sales representatives' ability to manipulate rankings. But in an interview with the local paper, he said Yelp could better train the sales team to be "crystal clear about what you get and don't get."