New York—Primedia is selling About.com, a network of niche Web sites that it purchased in 2000 for $690 million in stock, according to a story in Tuesday’s New York Times. Primedia has sold a number of assets over the past 18 months, including Modern Bride and Seventeen, to shore up its balance sheet. The New York Times reported that among the bidders for About.com are New York Times Co., Google, Yahoo!, Time Warner and Ask Jeeves. The asking price was reported to be between $350 million and $500 million. About.com/Primedia attracted 38.4 million unique visitors in December, ranking it No. 8 among the most visited-online properties, according to comScore Media Metrix.