Jammie Thomas, of Minnesota, was fined a total of $222,000 (£109,003). Jurors yesterday ordered her to pay six record companies $9,250 for each of 24 songs she illegally shared online.
The fine could have totalled millions of dollars because the record companies alleged that the 30-year-old had distributed 1,702 songs online through the Kazaa file sharing application in violation of their copyrights.
"This does send a message, I hope, that downloading and distributing our recordings is not OK," Richard Gabriel, the chief lawyer for the music companies, said.
Thomas and her lawyer made no comment as they left the court.
During the three-day trial, the record companies - Sony BMG, Arista Records LLC, Interscope Records, UMG Recordings, Capitol Records and Warner Bros Records - presented evidence they said showed the copyrighted songs were offered by a Kazaa user with the screen name of tereastarr.
Their witnesses, including officials from an internet service provider and a security firm, said tereastarr was using a computer that belonged to Thomas.
Record companies have filed around 26,000 lawsuits over file sharing since 2003, but this was the first case to go to trial. Many other defendants have settled by paying the companies a few thousand dollars.
Record companies say file sharing has hurt sales because it allows people to obtain music for free.
The Recording Industry Association of America says lawsuits have deterred illegal file sharing, although the number of households downloading music has risen from 6.9m a month in April 2003 to 7.8m in March 2007.
"This case has put [file-sharing] back in the news," Cary Sherman, the president of the RIAA, said. "Win or lose, people will understand that we are out there trying to protect our rights."
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