Major Internet portal site operator Yahoo Japan Corp. said Tuesday its group net profit for the fiscal second quarter more than doubled to 5.91 billion yen, powered by record advertising revenue.

The company, 41.9 percent owned by Softbank Corp., also issued its first earnings forecast, projecting its group net profit for the full year through March to grow at least 80 percent to 22 billion yen.

Consolidated sales during the July-September period jumped 61 percent to 17.55 billion yen, the company said.

It attributed the strong quarter to the record ad revenue, which grew nearly 60 percent from year earlier to 4.8 billion yen, despite the harsh business environment.

Company officials said the introduction of memory-intensive moving banner advertisements and promotional campaigns in areas such as IT, real estate and human resources, attracted clients during an otherwise thin market season.

"In a mid- to long-term perspective, there is still large room for the Internet ads to grow," said Masahiro Inoue, president and chief executive of Yahoo Japan.

Its auction business logged a hefty 80.6 percent year-on-year growth in revenue to 4.85 billion yen during the quarter.

The firm said transactions have been heavy since mid-September, with the number of auction listings standing at 4.47 million as of the end of the month.

Sales at Yahoo Shopping increased 30.5 percent to 1.54 billion yen during the same period.

To expand its virtual mall to catch up with dominant industry leader Rakuten Inc., Yahoo Shopping has started to invite small stores with low recognition to set up shop.

The number of stores in the site grew 135.4 percent to 565 during the three months, the company said.

Yahoo Japan also announced its shares will be traded on the first section of the Tokyo Stock Exchange starting next Tuesday. They are currently listed on the Jasdaq over-the-counter market.