Google has asked a US court to dismiss a $1bn (£500m) copyright action from entertainment giant Viacom Media, saying it is a threat to the internet.
Viacom owns a number of well-known brands
Viacom, owner of MTV and Nickelodeon, claims Google's video-sharing website YouTube uses its shows illegally.
In action launched in March, Viacom alleged that about 160,000 unauthorised clips of its programmes had been uploaded onto YouTube.
But Google has denied it is involved in "massive" copyright infringement.
In a submission filed with a San Francisco court, Google cited the Digital Millennium Copyright Act (DMCA) law from 1998, which state that internet companies were not responsible for what net users put on websites.
"By seeking to make carriers and hosting providers liable for internet communications, Viacom's complaint threatens the way hundreds of millions of people legitimately exchange information, news, entertainment, and political and artistic expression," Google said.
It added that it "respected" intellectual property and that it went "above and beyond" its legal obligations to protect that.
When launching the legal action, Viacom said that YouTube's strategy had been "to avoid taking proactive steps to curtail the infringement on its site".
"Their business model, which is based on building traffic and selling advertising off of unlicensed content, is clearly illegal and is in obvious conflict with copyright laws," it added.
In February Viacom, which also owns cable networks VH1 and Comedy Central, told YouTube to remove 100,000 "unauthorised" clips.
Viacom said its demand came after YouTube and Google failed to install tools to "filter" the unauthorised video clips following negotiations.
The soaring popularity of YouTube has led traditional media to worry that the displaying of clips from their programmes - without compensation - will lure away viewers, and, as a result, advertising revenue.
Google, which paid $1.65bn for YouTube last year, has been trying to win permission from media companies to broadcast output legally on YouTube in exchange for payment, avoiding the threat of legal action.