Nov. 24 (Bloomberg) -- European Union regulators dropped a four-year-old investigation into Qualcomm Inc. after companies that accused the chipmaker of charging excessive royalties on technology patents withdrew their complaints.

"All complainants have now withdrawn or indicated their intention to withdraw their complaints," the European Commission said in a statement today. "In view of this, the commission doesn't consider it appropriate to invest further resources in this case."

The end of the case means Qualcomm, the world's biggest maker of chips for mobile phones, will avoid a fine or the possibility of being forced to cut royalty fees. In the most recent quarter, 74 percent of Qualcomm's operating income came from technology licensing.

The commission, based in Brussels, began probing Qualcomm's patent royalty rates for third generation or "3G" technology, after a 2005 complaint by Nokia Oyj, Broadcom Corp., Texas Instruments Inc., Ericsson AB, NEC Corp. and a Matsushita Electric Industrial Co. unit. Nokia and Broadcom withdrew their complaints after reaching separate settlements with San Diego- based Qualcomm.

Ericsson said in a statement that it's withdrawing the complaint and continuing "its ongoing dialogue with competition authorities around the world in relation to Qualcomm's licensing practices."

Qualcomm said in an e-mailed statement that it's "extremely pleased" that the case was closed.

Royalty Rates

The probe focused on whether Qualcomm set "unreasonably high" royalty rates for patents after they had been adopted as part of Europe's 3G standard, which allows high-speed downloads of videos and music on handsets.

The commission said in the statement that "such assessments may be very complex, and any antitrust enforcer has to be careful about overturning commercial agreements."

The commission's case had faltered in recent months with EU Competition Commissioner Neelie Kroes seeking an internal review after her in-house legal and economic teams said they opposed filing a complaint over the issue.

The complainants had urged the commission to send an official complaint, known as a statement of objections, to Qualcomm, outlining how overcharging royalty rates harms consumers.

Business Practices

Boston-based CRA International Inc. said in a report last year in support of the complainants that Qualcomm's royalty rates of as much as 5 percent will cause consumers to overpay by at least 4.35 billion euros ($6.5 billion) worldwide through 2012.

Qualcomm said in the statement that consumers have benefited from its business practices in the past four years, resulting in "technological advances, greater choices and lower prices."

The commission could restart the investigation if another complaint is filed.

Japan's Fair Trade Commission said in September that Qualcomm coerced Japanese mobile-phone makers into agreements that prevented them from asserting their intellectual property rights, impeding fair competition. The FTC ordered Qualcomm to rescind the restrictive provisions.

NEC said in a statement that it withdrew the EU complaint because the Japanese order "contains important principles for the licensing of essential patents for standards."

Qualcomm was fined 260 billion won ($220 million) on July 23 by South Korea's antitrust agency for deterring competition through unfair fees. Qualcomm is appealing the fine.

To contact the reporter on this story: Matthew Newman in Brussels at Mnewman6@bloomberg.net.