<br /> On Friday, data-sharing business Dropbox Inc filed for an initial public offering of up to $500 million with the U.S. Securities and Exchange Commission.<br />The company said it plans to have its common stock listed on the Nasdaq under the ticker symbol "DBX".<br />Dropbox started as a free service to share and store photos, music and other large files. It is facing heated competition from technology giants including Alphabet Inc’s Google, Microsoft Corp and Amazon.com Inc.<br />Dropbox reported 2017 revenue of $1.11 billion. <br />
