Mplus won a final victory in a legal dispute over a key patent in the secondary battery assembly process. Mplus said on July 20 that the Supreme Court's First Civil Division on July 16 dismissed appeals by both sides in its lawsuit seeking an injunction against patent infringement by Seongwon Enertech, formerly Yuil Enerttech. The appellate ruling, including 11 billion won in damages, was finalised.

The case involved Mplus' patent No. 1329073 for an "electrode stacking device for secondary batteries". An electrode stacking device is equipment used in a core process of stacking cathode and anode materials alternately in the secondary battery assembly process. The Patent Court, the lower court, ruled on Feb. 12 that Seongwon Enertech's product fell within the scope of the patent rights (claims 1 and 5) and found for Mplus.

The Supreme Court, in a unanimous opinion by the justices involved, rejected Seongwon Enertech's claims denying the patent's inventiveness and seeking to withdraw a judicial admission. It found no errors that affected the ruling, such as a misunderstanding of legal principles or insufficient review, in the lower court's judgment. On the calculation of damages, it also found it lawful to recognise a reasonable amount of damages under Article 128(7) of the former Patent Act.

Seongwon Enertech is currently undergoing corporate rehabilitation procedures and has become obligated to include Mplus' 11 billion won claim in its rehabilitation plan. Mplus plans to continue legal steps to preserve its claim during the rehabilitation process.

An Mplus official said, "This final Supreme Court victory is the result of the Supreme Court also officially recognising our core technological capabilities and intellectual property rights built up through long-term research and development." The official added, "We will continue to strengthen our competitiveness in the global secondary battery equipment market through technological innovation, while taking a more active role in protecting our intellectual property rights."