Rakuten Marketing, part of Japan-based e-commerce operator Rakuten Inc., has bought PopShops for an undisclosed sum. The Seattle-based company sells technology that sends product data to comparison shopping and coupon sites, blogs and loyalty programs.

The acquired company becomes Rakuten PopShops and stays in Washington state. Its employees report to Rohinee Mohindroo, PopShops president. Rakuten says the acquired company serves some 4,000 advertisers and 25,000 web site publishers.

“Having built a long-standing partnership with PopShops, we were already impressed with the quality of its analytics engine and ability to help drive online sales,” says Yaz Iida, CEO of Rakuten Marketing. “Through this acquisition, we’ll continue to outpace the competition and strengthen our assets across all of the vital areas of digital marketing that will benefit from PopShops’s powerful analytics engine.”

Rakuten Marketing is a new group within the larger organization, a spokeswoman says. “Rakuten Marketing includes technology tools and services for affiliate marketing (via LinkShare), retargeting and display (MediaForge), search marketing, lead generation, and loyalty,” she says.

The deal represents the latest e-retail and online marketing acquisition for Rakuten, which in June launched its e-commerce operation in Austria.