Iljin sued by US Synthetic for patent infringements

Iljin Diamond has been sued in the US for patent infringement.

Industrial diamond firm US Synthetic has filed two lawsuits against Iljin Diamond and Iljin Holdings __ one on November last year to the southern district court of Texas and another in December to the International Trade Commission.

US Synthetic claimed in its lawsuits that Iljin used its patents without permission.

Iljin Diamond’s subsidiaries, Iljin Japan, Iljin Europe, Iljin China and Iljin USA were also named in the lawsuit. In total, six affiliates and 21 overseas subsidiaries of Iljin Group were named in the alwsuits.

Iljin Holdings owns a 50.07% stake in Iljin Diamond and is its biggest shareholder. 

US Synthetic claimed that its South Korean counterpart infringed on its patents on polycrystalline diamond compact and method to manufacture them. The diamonds are used oil and gas drilling equipment. US Synthetic also has related patents registered in South Korea. 

This is the second time Iljin is facing legal battle over industrial IP in the US. It settled a trade secret lawsuit with General Electric back in 1994. 

Iljin is yet to react to US Synthetic’s claim, publicly or legally. Conventionally, companies counter sue each other in these situations.

Iljin Diamond is the parent company of Iljin Composites, which is preparing for a listing on KOSDAQ. The patent lawsuit is expected to cost millions of dollars for the company once they start. Iljin Diamond owns an 86.9% stake in Iljin Composites.

Iljin Diamond dominates the industrial diamond market with DI of the US and E6 of the UK, but profitability of the business isn’t what it use to be. Last year, Iljin Diamond recorded 168.6 billion won in sales and 9.5 billion won in operating income. Operating income was down by 31.2% from 2019.

Iljin Composites is the exclusive supplier of hydrogen fuel tank to Hyundai Motor and Kia.