NEW YORK (Reuters) - English soccer's Premier League Ltd and music publisher Bourne & Co said on Monday that eight more parties have joined their lawsuit charging Google Inc and its YouTube online service with deliberately encouraging copyright infringement.

The new parties include the National Music Publishers' Association, which is the largest U.S. music publishing trade association, the Rugby Football League, the Finnish Football League Association and author Daniel Quinn.

Video programming owners have teamed up against YouTube, charging the top online video service with encouraging copyright infringement to generate public attention and boost traffic to its site.

Google has said it is abiding by existing law that protect Internet services from being liable for what is on their networks so long as they respond promptly to complaints.

MTV Networks owner Viacom Inc sued Google and YouTube in May for $1 billion for copyright infringement and demanded the removal of hundreds of thousands of Viacom video clips that were uploaded without permission by users.

"The clear and growing message to YouTube and Google is simple: their callous and opportunistic business model is contrary to right, contrary to law, and must and will be stopped," Premier League spokesman Dan Johnson said in a statement.

Robert Tur, the broadcast journalist who filmed the attack on Reginald Denny during the 1992 L.A. Riots, plans to withdraw his earlier suit against YouTube and join the proposed class action suit as a plaintiff.

The proposed class action complaint was originally filed in New York on May 4, 2007 in the U.S. District Court for the Southern District of New York.

Responding to the original suit in May, Google said: "These suits simply misunderstand the Digital Millennium Copyright Act, which balances the rights of copyright holders against the need to protect Internet communications and content."

Google did not have immediate comment on the new parties joining the suit.

(Reporting by Kenneth Li)
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