Adaptix Launches IPR Salvo at Clearwire

Adaptix Inc. has filed a patent infringement complaint against Clearwire LLC (Nasdaq: CLWR) and Sprint Nextel Corp. (NYSE: S), alleging that the operators are infringing on its patents by “offering WiMax services to customers” in compliance with Institute of Electrical and Electronics Engineers Inc. (IEEE) fixed and mobile 802.16 standards.

The complaint focuses on six patents Adaptix has been awarded related to the orthogonal frequency-division multiplexing (OFDM) technology that underpins both WiMax and LTE (long-term evolution) wireless broadband. (See 4G or Not 4G?) Adaptix filed the original complaint with the Texas Eastern District Court on Dec. 1, 2008. The firm is looking for an as-yet-unspecified amount of damages from the defendants.

"Clearwire Corp., Clearwire Legacy, and Sprint each has infringed and/or continues to infringe… Patent[s] by offering WiMAX (“Xohm” or “Clear”) services to customers in compliance with the 802.16 and 802.16e WiMAX standards, and by making, using and/or selling the supporting WiMAX network used to provide such WiMAX services,” writes Adaptix in its complaint. “Adaptix is entitled to recover from each Defendant the damages sustained by Adaptix as a result of each Defendant’s wrongful acts in an amount subject to proof at trial.”

None of the protagonists in this case are yet commenting on the complaint. Both Clearwire and Sprint said it's against their respective policies to comment on pending legal action. “Relative to this matter, I am unable to comment on pending litigation,” a spokesperson from Adaptix told Unstrung.

Base station vendor Adaptix has been awarded several patents in the U.S. and overseas related to OFDM over the years. (See Adaptix Awarded Patent and Adaptix Granted Patent.) The company originally referred to its technology as OFDMA/TDD, which works by assigning sub channels to individual users dynamically in time.

Adaptix has said in previous public releases that its patents “describe important capabilities for both mobile and fixed 4G wireless systems based on OFDMA. Such systems may include, but are not limited to, Mobile WiMAX (IEEE 802.16e), 3GPP’s Long Term Evolution (LTE), Next Generation Personal Handyphone System (NG-PHS) and 3GPP2’s Ultra-Mobile Broadband.”

Clearwire and Sprint are by no means the only operators currently offering services based on the IEEE 802.16 standard. DigitalBridge Communications Corp. and Towerstream Corp. (Nasdaq: TWER) both have significant WiMax footprints among many other smaller operators in the U.S. and beyond. (See WiMax: What's Working Now.)

— Dan Jones, Site Editor, Unstrung