Fairchild Semiconductor announced that the U.S. Patent and Trademark Office issued final rejections of patent claims from two of three unexpired Power Integrations patents involved in the four-year-old patent lawsuit between the two companies. The final rejections were issued following the re-examination of two Power Integrations U.S. patents: No. 6,107,851 and No. 6,249,876.
Besides the 2004 lawsuit, the '851 and '876 Power Integrations patents also are being asserted against Fairchild in another lawsuit filed by Power Integrations earlier this year. The majority of the claims from these two patents asserted in the 2008 lawsuit have now received final rejections. Fairchild is also suing Power Integrations on three Fairchild patents.
Fairchild Semiconductor said it was not surprised by the Patent Office actions, which it said helped validate its position that Fairchild does not infringe valid claims of Power Integrations' patents. The company said it was analyzing the Patent Office actions to determine their impact on the lawsuits, and that it will continue to vigorously contest the litigation with Power Integrations, including on appeal if necessary.
As to the third unexpired patent involved in the 2004 lawsuit (U.S. patent No. 6,229,366), it is also being re-examined by the Patent Office. For the second time, the Patent Office issued preliminary rejections of all claims asserted by Power Integrations. The fourth patent involved in the 2004 litigation has expired.