South Korea’s Hanmi Semiconductor and Hanwha Semitech have agreed to enter mediation in their ongoing patent infringement dispute over thermocompression (TC) bonders, equipment used in high-bandwidth memory (HBM) production.

The agreement, reached following a recommendation by South Korea’s Intellectual Property Trial and Appeal Board (IPTAB), has prompted the postponement of the fourth hearing in the case, which was scheduled for November 3 at the Seoul Central District Court.

The dispute centres on three patents held by Hanwha Semitech covering technologies used in HBM TC bonders: flux application inspection technology, blue-light inspection methods and flux planarization technology. Both companies have filed legal actions seeking to prevent the other from manufacturing and selling equipment allegedly infringing their respective patents.

Hanwha Semitech confirmed that both parties had agreed to participate in mediation following IPTAB’s recommendation last month. A company representative said Hanwha Semitech would approach the process in good faith.

Hanmi Semiconductor, however, has disputed Hanwha Semitech’s infringement allegations, maintaining that its technologies differ from those covered by Hanwha’s patents. This raises questions about whether the mediation process can produce an agreement or whether the dispute will return to court.

The legal battle could affect South Korea’s HBM equipment supply chain, particularly for SK Hynix, a major customer of both companies. TC bonders are essential to HBM manufacturing,stacking and bonding DRAM dies using controlled heat and pressure to produce memory components used in artificial intelligence accelerators.

Hanmi Semiconductor had previously been SK Hynix’s primary TC bonder supplier. However, Hanwha Semitech entered the market in March 2025, introducing competition into a supply chain that had largely been dominated by Hanmi.

The dispute began in December 2024, when Hanmi Semiconductor filed a patent infringement lawsuit against Hanwha Semitech. Hanwha Semitech subsequently challenged the validity of Hanmi’s patents through an invalidation trial in May 2025 and filed a countersuit in July 2025, seeking damages and measures including the disposal of allegedly infringing equipment.

The three patents under scrutiny concern the inspection of flux, an adhesive aid used during bonding; the wavelength of light sources, specifically the use of blue versus white light; and planarization squeegee technology. Given the technical complexity of the issues, the court had planned an unusual hearing format that would allow each company's legal representatives to deliver one-hour technical presentations.

Under South Korea’s Invention Promotion Act, industrial property rights dispute mediation can result in a settlement with the same legal effect as a judicial conciliation once both parties reach an agreement and a mediation protocol is established. However, either party can refuse to settle, in which case the mediation ends, and the existing court proceedings may continue.

An intellectual property lawyer noted that mediation has previously helped resolve patent disputes between semiconductor equipment companies, including a case in June 2025 that resulted in patent sharing and joint development. However, such outcomes depend on both parties being willing to reach an agreement.

The lawyer added that the mediation body cannot compel either party to settle. If negotiations fail, the court is expected to resume proceedings, including hearings on the technical evidence and alleged patent infringement.

Hanwha Semitech may be seeking a practical resolution, potentially through cross-licensing or a financial settlement, to reduce litigation risks ahead of major customer deliveries. Resolving the dispute could help the company pursue new supply opportunities without the uncertainty of an ongoing patent battle.

The outcome could also influence competition in the HBM equipment market. A ruling in Hanmi Semiconductor’s favor could strengthen its position as a leading TC bonder supplier and make it more difficult for competitors to enter the market. Conversely, a negotiated settlement could open the door to technology-sharing arrangements or other forms of cooperation.

For now, the focus is on whether the two companies can find common ground through mediation. If they fail to reach an agreement, the existing court and patent invalidation proceedings may continue, with potential consequences for competition, technology development, and equipment procurement across South Korea’s growing HBM industry.

- Asia IP