Tessera sues Sony, Renesas over stacked ICs

The suit is concerned with U.S. Patent No. 6,885,106, and has been filed in the U.S. District Court for Delaware.

"We filed this suit to protect our intellectual property and our licensees in good standing. Sony and Renesas Electronics' license agreements have expired, yet they are continuing to sell products using our technology. Thus, they are infringing on our patents," explained Henry Nothhaft, chairman and CEO of Tessera, in a statement. "Although discussions are ongoing with Sony and Renesas Electronics to secure their continued access to our semiconductor packaging technology through a licensing relationship with us, these discussions have not sufficiently advanced, thus necessitating this lawsuit."

Tessera noted that this patent is not U.S. Patent No. 5,663,106 asserted in the U.S. International Trade Commission Investigation No. 337-TA-630 (DRAM ITC Action) which covers the encapsulation of an IC.

Tessera has also filed a complaint against UTAC (Taiwan) Corp., this time in the U.S. District Court for the Northern District of California. The case claims breach of contract and breach of the covenant of good faith and fair dealing, and seeks declaratory relief. UTAC (Taiwan) Corp. is not covered by the license agreement between Tessera and United Test and Assembly Center Ltd, which was announced on March 1, 2010, Tessera said.