The legal scuffle between Viacom and Google’s YouTube, in the long-drawn-out copyright-infringement lawsuit, is apparently full on – with both the companies hurling accusations and counter-accusations back and forth!

The Google-Viacom copyright lawsuit dates back to 2007, when Viacom had complained in the US District Court for the Southern District of New York that the users of Google’s YouTube video-sharing site could upload over
100,000 video clips from Viacom-owned networks and movie studios – like BET, MTV, Comedy Central, Nickelodeon, and Paramount Pictures.

According to a Friday filing by Viacom - which is seeking $1 billion in damages -, Google co-founder Sergey Brin had supposedly said at one time that Google had calculatingly weakened its copyright compliance standards after its 2006-acquisition of YouTube, to “profit from illegal downloads.”

Meanwhile, YouTube said in its own Friday filing that said it was legally impervious to Viacom’s copyright-infringement allegations largely because Viacom itself had surreptitiously been uploading its own videos to YouTube.

Google said in its blog post: “Given the broad scope of marketing, YouTube could not be charged with knowledge of infringement merely because it came across a video that was clearly from a professionally produced television show or movie.”

The respective filings of both the companies, which urge a New York judge to rule in their favor before trial, were supported by thousands of documents they turned over to one another as part of the discovery stage of lawsuit.