Visa Inc, the No. 1 credit-card company, earned 465.1 million U.S. dollars last year according to a regulatory filing that gave investors a first look at the company's books ahead of a proposed initial public offering.

Operating revenue was 3.9 billion dollars and operating expenses were 3.19 billion dollars for the fiscal year ended September 30, according to the filing on Friday, which details a reorganization of the San Francisco-based company. Profit was 525.9 million dollars in the six months ended March 31 as Visa's operating margin almost doubled, Bloomberg News said.

Visa announced in October it would combine most of its global businesses and sell shares sometime next year to become more competitive. Investors have bid up shares of MasterCard Inc, the second-biggest card company, more than 330 percent since their debut in May 2006, and Morgan Stanley is completing a spinoff of the Discover card unit this week.

"The IPO is going to be highly popular among investors after the success of MasterCard," said Craig Maurer, an analyst at Calyon Securities USA Inc. "It's going to generate significantly larger buzz than MasterCard. That's the benefit of coming second, and Visa clearly has the edge in size."

Visa didn't set prices or timing for the share sale. While the filing said the offering will raise 1.54 billion dollars, the figure is used to calculate the registration fee for the company and the actual sum raised may be higher. Maurer said the share sale could ultimately raise more than 25 billion dollars.

Visa is combining its businesses excluding Europe to save money, facilitate the share sale, streamline decision-making and make acquisitions easier, the filing said.

The company's operating margin swelled to 34 percent in the six months ended in March from 18 percent in the fiscal year that ended in September.

Visa and MasterCard, based in Purchase, New York, collect fees from retailers on every transaction that moves through their networks. Merchants have charged both issuers with conspiring to impose inflated rates, leading to federal antitrust lawsuits. In the filing, Visa said it's facing about 50 class-action and individual antitrust suits brought on behalf of merchants.

Some of the proceeds from the share sale will be used to cover settlements or judgments tied to litigation, Visa said.

Visa, MasterCard and banks including Citigroup Inc agreed in July 2006 to pay 336 million dollars to their customers to settle antitrust lawsuits over currency conversion fees charged on foreign transactions. The filing said Visa agreed to pay 100 million dollars to settle federal actions and 20 million dollars for related California cases.