Square on Wednesday announced that it had registered with the Securities and Exchange Commission for its long-expected initial public offering. A startup that specializes in electronic payments, Square has been operating in the red. It plans to raise up to $275 million in its IPO, it disclosed. However, market conditions currently are not considered very favorable for IPOs. Square’s news made a few heads turn, coming just days after cofounder and CEO Jack Dorsey announced a big move at Twitter — which he also cofounded and where he’s also CEO.