Wikipedia
PortalPlayer, founded in 1999, was a fabless semiconductor company that supplied system-on-a-chip semiconductors, firmware and software for personal media players. The company handled semiconductor design and firmware development, while subcontracting the actual semiconductor manufacturing to merchant foundries.
It gained recognition as the company with which Apple contracted for development of the original iPod. The company went public with an IPO in November 2004 and traded on the NASDAQ under ticker symbol PLAY. Sales to Apple grew to 90% of the company's gross revenue, which ultimately hurt the company when Apple switched media processor chip vendors in its iPod lines.
On January 5, 2007, Nvidia Corporation announced that it had acquired PortalPlayer, Inc. for about $357 million.