Yelp sales reps have promised to suppress bad reviews of restaurants and other businesses that pay to advertise on the popular citizen-reviewer site–and have removed positive reviews of others that refused to play ball, several business owners allege in an expose fresh from northern California’s East Bay Express. Many of the complaints are issued by anonymous sources, but some come from folks who spoke for attribution, such as:

“Robert Gaustad, co-owner of Bobby G’s Pizzeria in Berkeley, said that about a year ago a Yelp sales rep offered to ‘move good reviews to the top to make us look better.’ Since declining to advertise, approximately fifteen to twenty of his restaurant’s reviews — mostly positive — have been removed for reasons he can’t figure out.

“Gaustad said his complaints have gone unheard but that a Yelp sales rep told him his complaints would be heard if he advertised.”

And:

“One San Francisco merchant said a Yelp sales rep rearranged the reviews on his restaurant’s page to entice him into advertising. Greg Quinn, general manager of Anabelle’s Bar and Bistro in San Francisco (168 reviews, 3.5-average star rating), said that around January 2007, a Yelp sales rep was trying to get him to advertise. Quinn said he subsequently noticed that some of his negative reviews had moved further down on the page. ‘It was clearly … a sales tactic’ said Quinn, who added that the rep called him up and asked, ‘Did you notice what I did? Well, we can keep doing that for you.’”

More:

“During interviews with dozens of business owners over a span of several months, six people told this newspaper that Yelp sales representatives promised to move or remove negative reviews if their business would advertise. In another six instances, positive reviews disappeared — or negative ones appeared — after owners declined to advertise.”

Yelp officials deny manipulating content to cater to advertisers or punish those who declined to buy sponsorships:

“Chief Operating Officer Geoff Donaker said advertisers and sales representatives don’t have the ability to move or remove negative reviews. ‘We wouldn’t be in business very long if we started duping customers,’ he said.

Yelp officials say any perception problems stem from the fact that advertisers can pick a favorite “sponsored” review to appear at the top of their listing:

“Donaker conceded that Yelp could do a better job of training its sales team to be ‘crystal clear about what you get and don’t get.’”

Might be a wise move.

As Anya Kamenetz, who knows a thing or two about Yelp and the “reputation economy,” notes on Fast Company’s blog, “The site has a legal right to do whatever it wants with the reviews and ratings on its site, whether user-submitted or written by employees. But if the company wants to reach profitability it better figure out a way to get more transparent and trusted–fast.”

It’s too late for Sen. Burris, but there’s still time for Yelp to heed this sage advice.

For more on Yelp, read “Night of the roundtable,” “The critical condition,” and “Amateur hour.”