On November 17, shares of South Korea’s leading high-end PCB manufacturer ISU Petasys (KRX: 007660) closed at KRW 131,500, up 18.36 percent for the day and 80.93 percent since early October. The rally far outpaced the 19.34 percent gain in the KOSPI Index during the same period and also surpassed the increase seen in major semiconductor names such as SK Hynix (up 74.39 percent) and Samsung Electronics (up 19.90 percent).

Another Korean PCB supplier, Korea Circuit, also surged 20.86 percent on the same day, closing at KRW 32,150.

Market analysts attribute the sharp rise to expectations that the AI supercycle will continue to drive explosive semiconductor demand—thereby lifting demand for high-performance PCBs used to transfer ultra-high-speed electrical signals from chip to system without distortion.

Stronger Penetration Into U.S. Tech Giants Boosts Earnings

ISU Petasys supplies multilayer boards (MLBs) for semiconductor applications to major U.S. technology companies, including NVIDIA, Google, and Microsoft. As its penetration among these customers deepens, the company’s profitability has strengthened significantly.

In the third quarter of 2025, ISU Petasys reported:

 ● Sales: KRW 296.1 billion (approximately USD 201.88 million, CNY 1.435 billion) 

 ● Operating profit: KRW 58.4 billion (approximately USD 39.82 million, CNY 283.06 million)

Compared with the previous quarter, revenue grew 22.7 percent, and operating profit rose 38.7 percent, setting new quarterly records.

Brokerages and Global Institutions Raise Target Price

On November 17, six major Korean securities firms—including NH Investment & Securities, Meritz Securities, and SK Securities—simultaneously raised their target prices for ISU Petasys.

Global investment bank J.P. Morgan also lifted its target price from KRW 95,000 to KRW 135,000, citing faster-than-expected increases in the average selling price of MLBs and the company's record-breaking third-quarter results.

Valuation Concerns Emerge Despite Strong Momentum

Some analysts, however, have raised concerns that the valuation is rising too quickly.
Brokerages such as Hana Securities and Kiwoom Securities now apply price-earnings ratios of 40x and 42x, respectively, when calculating the company’s fair value—levels seen as aggressive for the PCB sector.