Calling all fintech startups, Japanese e-commerce giant Rakuten is keen on you… so keen that it has officially launched a $100 million fund dedicated to supporting startups in the financial sector. I use the world “officially” because the fund, and its Managing Partner Oskar Mielczarek de la Miel, have been busy doing deals for some time — including a $12 million Series B round for Latin America-based Uber rival Cabify , a Series C for UK-based Currency Cloud , and bitcoin enabler Bitnet . Rakuten already runs Rakuten Ventures, a $100 million fund that invests across a range of verticals , but now it is literally doubling down on finance. Rakuten Ventures has done most of its deals in Asia but it is global in scope. The fintech fund, however, is more focused on Western markets, with plans to follow-on and invest in portfolio companies as well as find and back new mid-stage startups. “The fund will target investments in startups and growth companies primarily in the U.S. and Europe and build on the success of previous fintech investments made by Rakuten,” the company said in a statement. “While the fund’s immediate focus will be on companies based in fintech centers such as London, San Francisco, New York and Berlin, Rakuten FinTech Fund plans to gradually expand operations around the globe,” Rakuten added. So there will be opportunities for those in Asia and other emerging markets over time. Rakuten is best known for its e-commerce business — which has expanded globally with acquisitions deals like Ebates ($1 billion) and Overdrive ($410 million) — but, in its native Japan, it operates a number of top financial businesses, too. Its domestic business includes internet banking, credit cards, insurance, securities and asset management — with some of those services also available overseas. […]