“We are very pleased with InterDigital’s outstanding contributions on this breakthrough technology,” remarked Dr. Jae W. Byun, CTO of MNO Biz of SK Telecom. “This program is directly aligned with SK Telecom’s vision of an all IP, multi-radio access network.”

SK Telecom operates a nationwide UMTS network and has announced plans to expand its advanced mobile network across the country, building facilities for WiBro services throughout major cities in South Korea. SK Telecom entered into an agreement with InterDigital in 2006 to develop a network interoperability solution for its UMTS and WiBro networks, based on InterDigital’s leadership in next generation mobility standards, such as 3GPP UMTS and IEEE 802.21. In 2007, InterDigital successfully delivered to SK Telecom the system design and the software solution for mobile devices.

Under the extended collaboration, InterDigital will make further improvements to the existing handover capabilities, adding full two-way handover between WiBro and UMTS, as well as two-way handover between WiBro and cdma2000. In addition to the technology development, the amended agreement provides for potential collaboration on future projects.

“We are pleased SK Telecom, a pioneer in the deployment of visionary wireless broadband services, has chosen to expand our collaboration on the development of seamless handover between different wireless networks,” said Mark A. Lemmo, Executive Vice President, Business Development and Product Management, InterDigital. “Our modular architecture is ideally suited for adding innovative services and capabilities that benefit SKT and its customers.”

About SKT

SK Telecom is Korea’s leading mobile communications company with more than 20 million subscribers. SK Telecom successfully commercialized the world’s first CDMA cellular phone service and launched the world’s first IMT-2000 third generation service. The company is listed on the Korean Stock Exchange, the New York Stock Exchange and the London Stock Exchange. For more information about SK Telecom, please visit www.sktelecom.com or email at press@sktelecom.com.

About InterDigital

InterDigital designs, develops and provides advanced wireless technologies and products that drive voice and data communications. InterDigital is a leading contributor to the global wireless standards and holds a strong portfolio of patented technologies which it licenses to manufacturers of 2G, 2.5G, 3G, and 802 products worldwide. Additionally, the company offers baseband product solutions and protocol software for 3G multimode terminals and converged devices, delivering time-to-market, performance and cost benefits. For more information, visit the InterDigital website: www.interdigital.com