The company raised just over $344 million (£215 milllion) by selling 12.3 million shares today. MP3.com, which lets Internet users download news and MP3-formatted music, had put a price tag of $11 (£7) per share earlier this month.
Today, the company upped its estimate to $26 (£16), and boosted it again to $28 per share -- thanks to the US appetite for Cyber stock.
Over the past 10 months, the Internet music market has rarely been out of the press. In the last few day, the industry has seen a range of deals and announcements including Universal agreeing to offer content for download onto portable players and MTV taking a stake in Diamond Multimedia subsidiary RioPort.
Today's sale represents an 18 percent stake of MP3.com and gives the company a market value of $1.86bn (£1.16bn).
However, the company, founded Michael Robertson in 1997, has never made a profit and some analyst fear MP3.com shares will dive to less than $10 in six months.