Rakuten Inc. has acquired Slice, a shopping application that helps consumers keep track of their online shopping.

Terms of the buy were not disclosed. Rakuten, a Japanese company that operates online marketplace sites around the globe and has made numerous e-commerce investments in recent years, first invested in Slice last year, leading a $23 million funding round.

Slice’s shopping app, launched in 2011, organizes the order confirmations and shipping notifications that e-retailers e-mail to consumers after they purchase. Consumers let the Slice application access their webmail accounts.

“We couldn’t have found a better partner as we grow our business and product portfolio,” writes Slice founder and CEO Scott Brady in a blog post announcing the purchase. “Joining forces with Rakuten now enables us to exponentially increase our ability to develop the technology and products to bring that transformative vision to life more quickly and at a scale beyond what we could achieve independently.” Brady goes on to say Slice will operate as a stand-alone business and retain current management.

Rakuten had no immediate comment on why it purchased Slice or what it intends to do with it.

Rakuten, whose Rakuten Ichiba marketplace is the leading e-commerce site in Japan, has invested billions in recent years in e-commerce and online marketing companies in North and South America, Asia and Europe. The company’s global e-retail sites and shopping portals accounted for $18 billion in sales in 2013, while the company reported revenue grew 29.5% to $4.9 billion and net income more than doubled to $412.6 million. In June, it announced plans to invest $100 million in technology start-ups in Israel, the Asia-Pacific region and the United States.

Rakuten’s Play.com is No. 28 in the 2014 Internet Retailer Europe 500.