Reviewed 11 September 2026, after Q2 results. Next review after Q3 earnings on 26 October 2026.
What it does
Amkor is the world's largest US-headquartered OSAT β Outsourced Semiconductor Assembly and Test. After a chip is made on a wafer, someone has to cut it out, package it, connect it and test it. Amkor does that for other companies' chips.
Its advanced packaging work covers high-density fan-out (HDFO), 2.5D and system-in-package (SiP). CEO is Kevin Engel.
Advanced packaging matters more for AI than it sounds. A modern accelerator isn't one chip β it's several placed side by side on one substrate. How they're joined together decides how fast the whole thing runs.
Bull case
- Record quarter. Q2 2026, reported 27 July: revenue $1.90B, up 25.6% on the year and 13% on the quarter. Every end market grew
- Margin is expanding fast. Gross margin 16.8%, up 480 basis points from 12.0%. Net income $173.8M and EPS $0.70 against $0.22 a year earlier β up 222%
- TSMC signed a 10-year deal on advanced packaging, expanding US capacity at Amkor's Arizona campus. Wafer fabrication and packaging in one flow
- NVIDIA is pre-funding the factory. A multi-year partnership where NVIDIA pays up front to expand Amkor's US capacity. A customer paying for your plant is the strongest demand signal there is
- Guidance points the same way. Q3 revenue $1.95β2.05B with gross margin 18.5β19.5%, and computing revenue expected to grow nearly 30% sequentially
- Government money behind it. A CHIPS Act agreement worth up to $407M, a 35% US investment tax credit, and up to β©150B (about $100M) in Korean grants
Bear case
- Free cash flow is negative. Minus $269.9M in the first half β $381.6M coming in against $688.4M of capital spending. Full-year capex is guided at $2.5β3.0B, more than the company's entire annual revenue a few years ago
- One segment is guided down. Q3 communications revenue is expected to fall by a high single-digit percentage, against normal seasonality. The reasons given were production moving to Vietnam, memory supply constraints, and changing build patterns
- Levered into the spend. $2.5B of debt against $2.5B of cash. Funded, but with no slack in a heavy capex cycle
- TSMC keeps the best work. Most leading-edge AI packaging is done in-house at TSMC (CoWoS), so Amkor plays in the tier below the highest-value work
- The commodity end is a price fight. ASE, JCET and others compete hard on cost
- Thin margins are structural. 16.8% is strong for an OSAT but low in absolute terms. This is a capital-heavy business by nature
Major customers
- NVIDIA β multi-year advanced packaging and test partnership for next-generation AI platforms, with a capacity prepayment
- TSMC β 10-year partnership. TSMC fabricates, Amkor packages, particularly in Arizona
- Apple and premium smartphone makers β SiP and high-density fan-out for mobile
- Automotive and industrial chipmakers β record segment revenue this quarter
- The broad fabless industry β anyone who designs chips but doesn't package them
What would change the view
- Gross margin trajectory β 12.0% to 16.8% to a guided 18.5β19.5%. This is the whole operating leverage story
- Computing segment growth β guided to roughly +30% sequentially in Q3
- Free cash flow β negative while the capex ramp runs. When does it turn
- Arizona progress and the pace of the TSMC and NVIDIA volume ramp
- Communications stabilising once the Vietnam migration is through
- CHIPS Act funding milestones actually being hit
Update log
- 11 Sep 2026 β Reviewed. No change to the thesis or the verdict.
- 14 Aug 2026 β Full review after Q2 2026 results. Added the NVIDIA capacity prepayment and the 10-year TSMC agreement to the bull case. Flagged negative free cash flow as the dominant risk.
Research and education only β not investment advice.