Viacom accused YouTube of displaying nearly 160,000 unauthorized clips from its cable networks, including MTV, VH1, Comedy Central and Nickelodeon, reported the Associated Press.
"YouTube's strategy has been to avoid taking proactive steps to curtail the infringement on its site, thus generating significant traffic and revenues for itself while shifting the entire burden -- and high cost -- of monitoring YouTube onto the victims of its infringement," Viacom said in the suit that was filed in U.S. District Court in New York.
Google, which now owns YouTube, said it was confident the site respects copyrights.
"We will certainly not let this suit become a distraction to the continuing growth and strong performance of YouTube," Google said in a statement.
Media outlets have expressed concern over YouTube displaying user-uploaded clips of television programs without compensation and possibly drawing viewers and advertisers away from TV. The producers of programs have also expressed concern over the widespread violation of copyright posed by YouTube.
The lawsuit came six weeks after Viacom demanded that YouTube remove some 100,000 unauthorized clips from its site after months of talks over licensing arrangements collapsed, according to the AP.
YouTube does not keep copyrighted material off its site but does remove content at the request of copyright owners.
"We've dealt with YouTube on a case by case basis to have content taken down," said a News Corp. spokesman, adding the company supports Viacom's right "to protect its own content in whatever way it needs to," reported Reuters.
The lawsuit is seen by many experts as the first in a possibly protracted legal battle over the future of YouTube and other video-sharing sites.
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