Dow Corning’s LED Optical Silicon Encapsulant patent 200480028707.8 has been ruled invalid by China’s State Intellectual Property Office Patent Reexamination Board on Dec. 17, 2014, according to KMT Technology (KMT) official website.

The board ruled Dow Corning’s complaint that the Chinese manfacturer’s KMT-1269 had infringed LED optical silicon encapsulant patent was invalid, according to the KMT statement. After an eight month long legal battle, the patent lawsuit had finally come to a conclusion.

Recap of patent infringement lawsuit

Dow Corning’s Shanghai office filed a patent infringement complaint against KMT on April 14, 2014 in Shanghai First Intermediate Court. The complaint accused the Chinese company’s KMT-1269 product had infringed Dow Corning’s ZL200480028707.8 patent.

"As a global leader in the development of advanced high RI optical silicone technologies, Dow Corning will always rigorously defend its intellectual property to ensure that our customers continue to receive the highest quality products and reliability we can provide to help them stay competitive in today's fast-growing LED market," stated Kaz Maruyama, global industry director, Lighting Solutions, Dow Corning in a press release on April 18, 2014. Prior to the legal trial in China, Dow Corning believed KMT had violated its multilayered intellectual property (IP) portfolio to protect its phenyl-based optical silicone encapsulants.

KMT responded by emphasizing the KMT-1269 is an in-house developed product on April 21, and would take necessary legal actions to protect company rights.

A request to invalidate Dow Corning LED patents was submitted by KMT to China’s State Intellectual Property Office Patent Reexamination Board on April 28. In KMT’s application, the company highlighted that many of the patented content had already been publicized in technology papers, and does not meet patent regulations of being innovative nor creative.

The board sent the documents to Dow Corning on Aug. 4, 2014, and the company amended the extent of its patent infringement complaint.

Due to changes in Dow Corning’s LED Optical Silicone Encapsulants patent complaint, the Shanghai First Intermediate Court was ruling on Sept. 16, 2014 was indecisive.

The Chinese manufacturer submitted its second request to invalidate Dow Corning patents to China’s State Intellectual Property Office Patent Reexamination Board on Nov. 13, 2014.

One month after, the board made an official announcement that Dow Corning’s ZL200480028707.8 patent lawsuit was ineffective.