Flexsys 6PPD Suit to Proceed in District Court (N.D. Ohio)

According to the Rubber & Plastics News (subscription required), the U.S. District Court for the Northern District of Ohio has recently allowed Flexsys America L.P. to proceed with a $20 million patent infringement lawsuit against Chinese chemical producer Sinorgchem Co.; its U.S. distributor, Akron-based Sovereign Chemical Co.; South Korean tire maker Kumho Tire Co. Inc.; and its U.S. subsidiary, Kumho Tire U.S.A. Inc.  The district court case had originally been stayed while a companion case was pending before the U.S. International Trade Commission (ITC).

Flexsys asserted in the ITC complaint that the above parties infringed on Flexsys’ U.S. Pat. Nos. 5,117,063 (the 063 patent), 5,608,111 (the 111 patent) and 6,140,538 (the 538 patent) related to N-(1,3-dimethylbutyl)-N’-phenyl-p-phenylenediamine (“6PPD”).  This chemical is a rubber antidegradant found in most tires sold in the United States.

On July 13, the ITC ruled that Sinorgchem violated Flexsys patents drawn to methods of manufacturing 6PPD and a precursor feedstock, 4-ADPA.  The ITC further ruled that Sovereign infringed by selling Sinorgchem’s versions of those products in the U.S.

Notably, the ITC exonerated Kumho, but Flexsys kept the tire maker and its U.S. arm in the lawsuit, stating the issues in the suit were different from those in the ITC case.

The limited exclusion order by the ITC may be viewed here:  Investigation No. 337-TA-533.

JW Note:  As a former rubber compounder in the tire industry (and thus being very familiar with 6PPD), I found this article to be of great interest . . . at the crossroads of my legal and technical expertise.  It will be interesting to watch how this case develops!