MEXICO CITY, May 12 — The Mexican media company Grupo Televisa said on Friday that it planned to bid for the Spanish-language broadcaster Univision along with five private investment firms, including one owned by the chairman of Microsoft, Bill Gates.

Univision, which is based in Los Angeles, is the leading media company in the United States aimed at the fast-growing Hispanic market. It put itself up for auction in February.

Televisa, the world's largest Spanish-language media company, provides most of the network's prime-time programming.

Although Televisa already owns 10.9 percent of Univision, the company's chairman, Emilio Azcárraga Jean, has been outspoken about his desire to own more.

But United States regulations limit foreign ownership of a broadcaster to 25 percent. Venevision, controlled by the Venezuelan billionaire Gustavo A. Cisneros, owns 13.3 percent of Univision.

Along with Televisa and Mr. Gates's firm, Cascade Investment, the groups doing the bidding are Bain Capital Partners, Blackstone Management Associates, Carlyle Investment Management and Kohlberg Kravis Roberts, Televisa said.

If Televisa seeks to increase its share in Univision to 25 percent, the bidders will have to find some way to work out how to buy or convert Mr. Cisneros's stake because total ownership can be no more than 25 percent, said one person close to the negotiations.

Negotiations are likely to take a couple of months. Many analysts expect that Univision is worth about $40 a share, or about $13.5 billion. But if another bidder enters the fray, the price could spike.

Still, Televisa is seen as crucial to any purchase of Univision.

The Televisa-led group has emerged as a bidder for Univision after reports in March that a consortium that included Providence Equity Partners and Madison Dearborn Partners was considered a possible buyer.

Univision is owned by A. Jerrold Perenchio, 75, who bought the company with Mr. Azcárraga's father and Mr. Cisneros in 1992.

The relationship between Mr. Perenchio and the younger Mr. Azcárraga, 38, has become fractured in the last year. Televisa has accused Univision of violating the company's programming agreement and Univision has countersued.

Univision shares closed up 30 cents yesterday, at $35.92. Shares were trading slightly above $30 in February, when news of a possible sale was first reported.