In a brief press release, Square announced it has finally closed its Series D round of funding, which includes Starbucks Coffee Company and Citi Ventures. A company spokesman confirmed that the round raised more than $200 million. (This includes $25 million that Starbucks announced last month.)

"One year ago, Square had approximately 150 employees and processed over $1 billion in payments on an annualized basis," Square said in its announcement. "Today, Square has over 400 employees and is processing over $8 billion in payments on an annualized basis."

The new round of funding puts total funds raised by Square around $340 million. According to Tricia Duryee at AllThingsD, insiders are pegging Square's value in the neighborhood of $3.25 billion.

Square said it expects to expand into international markets later this year. It will face competition in many of those markets, especially in Europe, where clones of the company's mobile POS solution, such as iZettle and mPowa (which even mimic Square's square-shaped card-reading dongle), have already begun setting up shop.

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