Seojin System: Share Price Up 86.0% Over a Year While Trailing Earnings Turn Negative

Thesis

The data supports a picture of a company whose share price has recovered strongly (1-month +15.5%, 3-month +5.2%, 1-year +86.0%) even as reported profitability has deteriorated. Revenue is large compared with the market cap, with a price-to-sales ratio of 1.9, but the trailing operating margin is -5.4% and net margin is -6.8%.

The filing list shows repeated changes of largest shareholder, 5%+ holding reports, debt guarantee decisions and a major sales or supply contract on 2026-10-12. The data gives no details on contract size, counterparties or the new shareholder, so their effect on earnings cannot be judged. Investor flow, foreign ownership, short balance and news data are not available.

Business overview

Seojin System is listed on KOSDAQ in the electrical equipment sector. It was founded on 2007-10-30 and listed on 2017-03-27, with 56,247,954 listed shares and CEO 전동규. The data does not describe its products or customers.

Revenue grew from ₩606.1B in 2021 to ₩787.6B in 2022, ₩778.7B in 2023 and ₩1.21T in 2024 (+55.9%). It then fell 12.1% to ₩1.07T in 2025. The trailing twelve months to H1 2026 reached ₩1.22T.

Financial analysis

These figures come from filed financial statements (DART). Operating margin was 9.6% in 2021, 5.6% in 2022, 6.3% in 2023 and 9.0% in 2024, then fell to 0.1% in 2025 (operating income ₩1.1B). The trailing figure is -5.4%, with an operating loss of ₩66.1B.

Net income was ₩84.3B in 2024 but a loss of ₩101.2B in 2025, and the trailing twelve-month loss is ₩82.8B. ROE moved from 12.3% in 2024 to -12.6% in 2025 and -8.9% trailing.

The balance sheet looks stretched. Liabilities to equity are 206.2%, borrowings are ₩397.8B, and cash is ₩47.8B. Trailing free cash flow is -₩534.6B, a large outflow relative to the market cap.

Valuation

The price-to-earnings ratio is not available because earnings are negative. Price-to-book is 2.4, versus 1.9 at the end of 2025. Price-to-sales is 1.9. EV/EBITDA is 69.0 on an enterprise value of ₩2.7T, which reflects very thin trailing EBITDA. No dividend yield is available.

Listed peers show price-to-book of 2.5 (Taihan Cable & Solution), 2.6 (LS Electric), 8.1 (Hyosung Heavy Industries), 9.3 (HD Hyundai Electric) and 9.8 (Sanil Electric). Seojin's 2.4 is at the low end of that range. Peer P/E ratios of 14.2 to 36.2 rest on positive earnings, which Seojin does not currently report. Older year-end multiples are mostly not available, so a comparison with its own history is limited.

Catalysts

• A major sales or supply contract was filed on 2026-10-12, though the data does not give its size or terms.
• An amended change-of-largest-shareholder filing on 2026-10-12 follows similar amendments on 2026-09-22 and 2026-09-14, so ownership control may be in flux.
• Several 5%+ holding reports (2026-09-07, 09-21, 09-23, 10-07) show continued changes in large holders.
• Debt guarantee decisions to a third party were amended on 2026-09-18 and 2026-10-02, which bear on the company's financial obligations.
• The next financial statements will show whether the operating loss narrows from the trailing -₩66.1B.

Risks

• Trailing operating and net losses (-5.4% and -6.8% margins) mean the business is not currently profitable on filed figures.
• Free cash flow of -₩534.6B against cash of only ₩47.8B and borrowings of ₩397.8B points to funding pressure.
• Liabilities to equity of 206.2% leave less room for further losses.
• Guarantees for a third party add potential obligations whose scale is not disclosed in the data.
• The share price sits 50.4% below its 52-week high of ₩83,300 but 93.9% above its low of ₩21,300, showing large swings, and flow and short-interest data are unavailable.

Closing view

The data shows a company with sizable revenue and a sharply higher share price over the past year, set against negative profits, heavy cash outflow and high leverage. Frequent shareholder and guarantee filings add uncertainty, while the new supply contract is a positive item whose financial effect is unknown. Price-to-book near the low end of its peer group is hard to interpret without positive earnings. Several key inputs, including investor flows, foreign ownership and news, are missing, so conclusions are limited to the filed financials and price data.

Model estimate of fair value

The valuation model has no estimate for this company yet (not enough data, or no positive value with the base case).

Report history

1. Oct 13, 2026InitiationSeojin System: Share Price Up 86.0% Over a Year While Trailing Earnings Turn Negative