Kim Dotcom, a German national also known as Kim Schmitz, will be held in custody in New Zealand until February 22 ahead of a hearing of a U.S. extradition application.

U.S. authorities claim Dotcom's file-sharing site, Megaupload.com, has netted $175 million since 2005 by copying and distributing music, movies and other copyrighted content without authorization. Dotcom's lawyers say the company simply offered online storage and that he will fight extradition.

"It could take some considerable time to get through the whole thing," said senior New Zealand lawyer Grant Illingworth, adding there were rights of appeal and procedural review to both sides.

Dotcom, 38, and three others, were arrested on Friday after a police raid at his rented country estate, reputedly New Zealand's most expensive home, at the request of the U.S. Federal Bureau of Investigation.

Under New Zealand's extradition law the prosecution must show there is enough evidence that would substantiate charges against Dotcom and the other accused of breaching local copyright laws.

"What the judge has to do is decide whether there is a prima facie case that would justify the person being put on trial if the offence had occurred in New Zealand," Illingworth said.

"If the evidence doesn't make out, what under New Zealand law amounts to a prima facie case, then the person walks away."

A 1970 extradition treaty between the United States and New Zealand gives the U.S. 45 days from the time of Dotcom's arrest to request extradition. The New Zealand Extradition Act, passed in 1999, gives the United States preferential status to access a streamlined process for making its request.

The judge who refused Dotcom bail said he could not assess whether the United States had a strong enough case against Dotcom, nor whether he had a good defense.

"All I can say is that there appears to be an arguable defense, at least in respect of the breach of copyright charges," Judge David McNaughton wrote in his judgment.

CIVIL MATTER

Copyright infringement and illegal file sharing are normally civil matters in New Zealand, but there is a provision for criminal charges and a maximum 5-year jail term for serious breaches.

Rick Shea, a partner at Lowndes Jordan in Auckland, said there were some differences between New Zealand and U.S. copyright law, in terms of knowledge, that could be an issue.

Douglas McNabb, a U.S. lawyer who specializes in extradition defense, said extraditions to the United States have to meet probable cause - the same standard that is required for making arrests in the United States.

Although the extradition hearing is not a test of guilt or innocence, McNabb said Dotcom's lawyers may argue they should be allowed a limited discovery process to show that probable cause has not been met.

Prime Minister John Key said the issues raised were serious and New Zealand would co-operate with the U.S. authorities.

"This is the largest, most significant case in Internet piracy so New Zealand is certainly going to work with the United States authorities to allow them to extradite Kim Dotcom," he said on TV3.

According to Shea, New Zealand has never had an extradition proceeding involving copyright law. "I wouldn't expect this to be sorted out quickly," he said.

AGGRESSIVE CHARGES

Anthony Falzone, Director for Copyright and Fair Use at Stanford Law School's Center for Internet and Society, said it was too early to comment on the strength of the case, but questioned whether some of the allegations in the indictment would actually push Megaupload outside the safe harbor provisions of the Digital Millennium Copyright Act.

The indictment "pushes some pretty aggressive theories", Falzone said.

The most recent Supreme Court case to deal with similar issues was in 2005. In MGM v Grokster, the U.S. court highlighted the importance of intent in determining if an Internet firm was liable for its users infringing copyright.

"A lot of the Megaupload case may also rise and fall on the question of intent," said Falzone.

With MGM, the court found the intent of the Internet company from the beginning was to build a tool to facilitate illegal sharing.

"Maybe that's what the Feds (FBI) think they have here, too," said Falzone.

(Reporting by Gyles Beckford in WELLINGTON and Rebecca Hamilton in NEW YORK; Editing by Lincoln Feast and Ian Geoghegan)

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