Software maker Openwave Systems filed a complaint against Apple and Research In Motion on Wednesday, alleging infringement of five of its patents relating to mobile Internet technology.

Openwave, which is seeking to turn around a loss-making business, said the iPhone and BlackBerry makers had infringed on its patents for technologies used to connect smartphones and tablet computers to the Internet.

Before filing these complaints, we approached both of these companies numerous times in an attempt to negotiate a license of our technology with them and did not receive a substantive response, Openwave Chief Executive Ken Denman said.

In the end, litigation is the only way we can defend our rights against these large companies that have effectively refused to license the use of the technologies we invented, Denman said.

Openwave's legal action is the latest such move in a mobile landscape that is increasingly cluttered with lawsuits as companies seek legal recourse to protect their products or force rivals to pay fees. The prices paid in recent patent sales has also spiked.

Openwave, which owns about 200 patents, filed the complaint at the International Trade Commission in Washington D.C. and also at a federal district court in Delaware.

The company said it expected a favorable ruling from the ITC, which would push RIM and Apple to pay very substantial licensing fees.

RIM declined to comment on Openwave's suit. Apple was not immediately available.

Shares of the Redwood City, California-based Openwave were up 30 cents at $1.77 on Nasdaq on Wednesday morning.

The move comes days after Openwave, which posted a net loss in its last financial year, said it had paid $12 million to Myriad Group to end all of that company's claims on its patents.

Openwave's software allows companies to analyze and optimize traffic on their wireless networks.

The ITC filing seeks to block Apple from importing its iPhone, iPod Touch and iPad into the United States, and to ban RIM from bringing in its Curve smartphone and PlayBook tablet.

(Reporting by Alastair Sharp in Toronto, additional reporting by Supantha Mukherjee in Bangalore; editing by Rob Wilson)

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