US record industry officials have already won 871 subpoenas to identify music pirates illegally downloading songs over the internet.
Hundreds of individuals are being targeted for copyright violation
More than 75 subpoenas are being granted every day, US courts said on Friday.
The subpoenas are part of the industry's battle to clamp down on music piracy, and have been spearheaded by the Recording Industry Association of America (RIAA).
They will force telecommunications companies to identify file-swappers, who are usually only known by their codenames.
The RIAA, which represents the major record labels, announced last month it would pursue individual users following a court ruling making it easier to track down copyright violators.
The RIAA has said it plans to send its subpoenas over the next eight weeks.
Users charged with piracy could face lawsuits for damages ranging from $750 (£480) to $150,000 (£96,100), which are applicable under US copyright laws.
The RIAA has said it is prepared to discuss settlements, however.
The RIAA had said it would go after internet users who had uploaded many songs, but some of the filed subpoenas cited as few as five representative songs. It has not said how many songs would justify a lawsuit.
"We would have to look at historic trends, but that is a very high number," said Alan Davidson of the Center for Democracy and Technology, a civil liberties group opposing the lawsuits.
"It doesn't sound like they're just going after a few big fish," he said.
The RIAA has said it plans to use software robots to search for copyright violations, as well as sending warnings to universities and businesses demanding they remove illegal material.
It has already been disrupting the file-sharing networks with fake files of its own which contain white noise.
But music fans are reacting with a new generation of file-sharing software that tries to prevent monitoring.
A version of "Kazaa-lite" says it can stop outside parties scanning email addresses and listing songs on individuals' hard drives.