The sites don't condone online piracy, she added. "But it's a reality and not our fault," she said. "We provide free hard disk space in the cloud. That's it."
Rapidshare questioned the methodology in the paper, saying MarkMonitor's numbers ignore the legal traffic on the website.
"The authors conclude that RapidShare has to be the biggest digital piracy site from looking at the number of page visits, totally ignoring the fact that millions of customers use the service for perfectly legitimate purposes," the company said. "Private customers use RapidShare to share their personal pictures, videos and documents or to make backup copies of their hard drives. Business clients rely on our services to exchange large files with colleagues at different sites."
Rapidshare customers who upload unauthorized material are "in the absolute minority," the company added. Rapidshare is working to educate policymakers about its business, the company said.
MarkMonitor stands by its classifications in the paper, said Te Smith, the company's vice president of communications. The paper acknowledges that some of the sites it classifies as involved in digital piracy offer takedown processes, but the action must be initiated by the content owners. "We believe the topic is important and deserves a healthy discussion," she said.
MarkMonitor employees hand-checked the sites before including their traffic numbers in the paper, she added. "We didn't want to be counting false positives," Smith said.
The Motion Picture Association of America said the MarkMonitor study shows the need for new legislation to protect copyright owners.
"As the report demonstrates, a small number of rogue websites are generating mind-boggling traffic in pirated content," Bob Pisano, MPAA's president and interim CEO, said in a statement. "Billions of visits to these easily searchable websites ... translate into billions in lost revenue and lost American jobs."
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