In its first foray into the U.S., Japanese portal Rakuten - which operates top-ranked sites for online shopping, travel, golf reservations, community, and greeting cards - is slated to acquire affiliate marketing firm LinkShare for $425 million in cash. It is the Tokyo-based company's largest deal to date, writes ClickZ. The deal is expected to close in 4-6 weeks. LinkShare will operate as a wholly owned subsidiary of Rakuten, and its senior management team will remain with the company.

According to Internet Retailer, LinkShare chairman and CEO Steven Messer said of the deal: "This is the first time we've heard about an Asian company coming to the U.S. to compete with Yahoo here."

Rakuten has a market capitalization of just under $10 billion and is considered the seventh-largest internet company in the world. Messer is also quoted by Internet Retailer as saying that Rakuten's intention is to "become a number-one player around the world, and to use LinkShare as a platform and a starting point to build a much bigger business in the U.S."

"LinkShare's performance-based marketing expertise across affiliate, search, and email capabilities provides Rakuten with an excellent first step to launch our U.S. operations and continue our international expansion," Hiroshi Mikitani, Rakuten's chairman and CEO, said in a statement. "We can leverage LinkShare's client relationships and technology advantages worldwide, so that LinkShare will be able to achieve significant growth in the future."

Messer said merchants and affiliates would benefit from increased volume when Rakuten takes the network worldwide. LinkShare has more than 500 clients, including J.C. Penney, 1-800-Flowers.com, American Express, Avon Products and Dell.