Lb Semicon

LB Semicon is an outsourced semiconductor assembly and test (OSAT) specialist whose core operations span bumping (forming metal bumps on wafer-level chips), wafer testing to screen individual chip performance, and back-end packaging processes.

In fiscal 2024, the semiconductor segment accounted for 97.0% of consolidated revenue on a controlling basis, with secondary-battery recycling making up the remaining 3.0%, and within the semiconductor segment bump-related sales made up the bulk of revenue.

The company has long been centered on display driver IC (DDI) back-end services, with Samsung Electronics and LX Semicon as key customers, resulting in a historically high customer concentration.

To diversify away from this structure, LB Semicon has been expanding into non-DDI areas such as power management IC (PMIC), CMOS image sensor (CIS), and application processor (AP)/system-on-chip (SoC) testing.

In February 2025 the company absorbed its affiliated packaging unit LB Rusem, establishing an in-house turnkey capability that covers chip-on-film (COF) packaging and final test at its Gumi plant.

In August 2025 it announced a turnkey partnership with ASE Korea, the world's largest OSAT operator, under which LB Semicon handles bumping and wafer test while ASE Korea handles packaging, around the same time it ramped up power-semiconductor back-end production for Renesas.

In early September 2026 the company disclosed its first product shipment to Qualcomm for AI data-center and automotive semiconductor applications, extending its non-DDI and overseas customer base.

Alongside these, it also runs a smaller secondary-battery material recycling business through a subsidiary formerly known as Jinsung Retec.

On an annual basis, revenue and profitability were solid in 2022 at KRW 524.6 billion and an operating profit of KRW 56.8 billion (10.8% operating margin), but performance deteriorated sharply in 2023 with revenue falling 20.5% to KRW 416.9 billion and an operating loss of KRW 12.7 billion.

Revenue recovered in 2024 to KRW 450.9 billion (+8.2%), yet the operating loss widened to KRW 18.8 billion and the controlling-interest net loss grew to KRW 22.2 billion.

In 2025, revenue rose further to KRW 479.8 billion (+6.4%), but the operating loss expanded sharply to KRW 39.8 billion (-8.3% margin) and the controlling-interest net loss ballooned to KRW 150.9 billion.

This reflected a large non-cash impairment charge recognized after the LB Rusem absorption merger, with a single quarter, 2025Q4, contributing a controlling-interest net loss of KRW 134.5 billion that weighed heavily on the full-year result.

Quarterly trends have since shifted noticeably: the loss narrowed in 2025Q3 to KRW 6.3 billion on revenue of KRW 125.6 billion, and by 2026Q1 the company posted revenue of KRW 134.3 billion with an operating profit of KRW 7.6 billion and a controlling-interest net profit of KRW 10.2 billion, marking a turnaround on both lines.

In 2026Q2 revenue rose further to KRW 144.9 billion with an operating profit of KRW 13.1 billion and a controlling-interest net profit of KRW 8.8 billion, sustaining two consecutive profitable quarters.

Capacity reductions among DDI back-end competitors that redirected orders toward LB Semicon, along with expanding non-DDI sales in power semiconductors, CIS, and AP testing, are cited as the main drivers of the recent improvement.

Worth noting alongside this, however, is that operating cash flow has shrunk sharply each year, from KRW 124.0 billion in 2022 to KRW 80.8 billion in 2023, KRW 52.0 billion in 2024, and KRW 9.5 billion in 2025.

The OSAT industry is generally viewed as a capital-intensive sector requiring large-scale equipment investment and years of accumulated customer trust, making it difficult for new entrants to break in.

Generative AI-driven demand and the expansion of AI accelerators have been improving results across the back-end industry, while rising utilization at IT OLED lines and the spread of AI PCs have supported stable growth in the DDI back-end market, with AI momentum extending from servers to PCs and smartphones and advanced packaging now exceeding the scale of the general packaging market.

Capacity reductions by some domestic DDI back-end competitors have also redirected order flow toward LB Semicon.

Notably, rather than competing directly with ASE, the world's largest OSAT operator, LB Semicon has chosen a collaborative division of labor, handling bumping and testing while ASE manages packaging under a turnkey arrangement.

Bump-line utilization stood at around 65.3% as of the first quarter of 2025, with room for improvement cited as cooperation and order volumes expand further.

That said, the company's continued reliance on DDI leaves its results tied to fluctuations in downstream IT set demand such as TVs, smartphones, and monitors, making the pace of non-DDI diversification a key variable for its future competitive position.

The company set a target of KRW 500 billion in revenue and a return to operating profit starting in 2025, and its 2026Q1 and Q2 results show it actually achieving that turnaround.

Over the medium to long term, management has set a vision of reaching KRW 1 trillion in back-end revenue and a top-10 global OSAT ranking by 2027, alongside a stated plan to raise its overseas revenue share from its current level of around 10%.

To fund this, the company issued a KRW 14.5 billion convertible bond (conversion price of KRW 4,285) in February 2026, followed by a rights offering of 12 million common shares (issue price of KRW 4,125) that completed its new-share listing in August 2026.

LB Semicon has said the proceeds from the rights offering will go toward new bump and back-end equipment investment to expand production capacity in stages to meet anticipated volume growth.

The initial Qualcomm shipment followed roughly two years of technical review, quality management system audits, and reliability qualification, and the company has indicated room for expanded cooperation going forward.

Expansion of the non-DDI and overseas customer base is also proceeding in parallel through Renesas power-semiconductor back-end production and the ASE Korea turnkey partnership.

That said, how quickly and how substantially these new lines and diversified customers translate into actual revenue and margin improvement is something that will need to be confirmed through upcoming quarterly results.