(Telecompaper) Mobile payments specialist Square has filed confidentially for an initial public offering (IPO), Bloomberg reported, citing people with knowledge of the matter said. Square has been working with Goldman Sachs, Morgan Stanley and JPMorgan Chase on the IPO, said the people, who asked not to be identified because the process is private. The company and banks involved declined to comment. Under the Jumpstart Our Business Startups Act, companies with less than USD 1 billion in revenue can privately file for an IPO with the US Securities and Exchange Commission.