The U.N. copyright agency on Wednesday reported a 20 percent jump in "cybersquatting" complaints last year, coming mainly from top tech firms, trendy fashion brands, Hollywood stars and sports personalities.

The agency registered 1,456 complaints for cybersquatting — or abusive registration of trademarks as Internet domain names — and the practice appears to be on the rise, said Francis Gurry, deputy director general of the World Intellectual Property Organization, or WIPO.

WIPO handles arbitration for over half of the world's cybersquatting disputes each year. Gurry said the rise highlighted the need for "vigilance by intellectual property owners."

"It is important to protect the integrity of market identity," he said. "If domain names are randomly attributed in new domains, intellectual property owners will be forced to compete with cybersquatters for their own trademarks — unless additional safeguards are introduced."

Most of last year's disputes have since been resolved, including cases brought by celebrities such as Morgan Freeman, Damien Hirst, Frank Gehry and Larry King, as well sports organizations including the Lance Armstrong Foundation, Italian soccer club Juventus and the English Premier League.

Web sites such as sony-ericsson.org and renaulttrucks.com, as well as fashion brands Ralph Lauren, Hugo Boss, Armani and Calvin Klein, were also targeted.

Cybersquatters often demand great amounts of money for the sale of Internet sites to people or firms with registered trademarks, Gurry said.

"It's a commercial model based on the number of hits on a site," Gurry explained.

Anyone can register a domain name on the Internet for a few dollars, which has led to so-called "cybersquatters."

The U.N. arbitration system, which started in 1999, allows those who think they have the right to a domain name to get it back without having to fight a costly legal battle or pay large sums of money.

It costs about $1,500 to file a claim at WIPO. The arbitration system cannot award financial penalties.

Previous celebrities to have won the Internet version of their names back through U.N. arbitration, including Morgan Freeman, Julia Roberts, Madonna, Nicole Kidman, Pamela Anderson, Pierce Brosnan and Carmen Electra.

In total, WIPO has received over 8,000 complaints, nearly half of which were filed by people or companies based in the United States. U.S. firms and individuals were also the targets of nearly half of all complaints.

France, Britain and Germany were next in filing the most cybersquatting complaints. But while the German and French were rarely accused of bad faith, the number of Chinese firms or individuals to come into the line of fire far outnumbered their compatriots filing claims.

Gurry said linguistic reasons partly explain the imbalance, because certain languages have much wider accessibility than others for cybersquatters.

With about 60 million registered domain names worldwide and the number still growing, he said cybersquatting would probably increase, but hoped that new measures would help stem the tide.

Since 1999, WIPO has decided in favor of the complainant in 84 percent of all cases.