Outsourced Assembly & Test companies

As of 2026-10-04, wafergraph tracks 21 Outsourced Assembly & Test companies across 6 countries; ASE Technology hold monopoly or leader positions. The largest by market cap is ASE Technology at $123.5B, and the 16 priced companies total $214.3B.

Data as of 2026-10-04 · market caps from the daily wafergraph pipeline; unpriced companies are listed but not summed

21 companies in the Outsourced Assembly & Test part of the semiconductor & AI value chain.

Market share

Outsourced Assembly & Test market share 2024

Companies

  • ASE Technology — World's largest OSAT, includes SPIL; key advanced packaging partner. leader · NYSE:ASX · $20.6B rev · Taiwan
  • JCET Group — China's largest OSAT (includes former STATS ChipPAC). major · SSE:600584 · $5.8B rev · China
  • Amkor Technology — Second-largest OSAT; building advanced packaging capacity in Arizona. major · NASDAQ:AMKR · $6.7B rev · United States
  • Tongfu Microelectronics — Chinese OSAT and AMD's main packaging partner via JV fabs. major · SZSE:002156 · $4.2B rev · China
  • King Yuan Electronics (KYEC) — Largest dedicated test house; heavy AI GPU test exposure. major · TWSE:2449 · $1.1B rev · Taiwan
  • Huatian Technology — Top-three Chinese OSAT provider. major · SZSE:002185 · $2.6B rev · China
  • Powertech Technology (PTI) — Memory-focused OSAT leader in Taiwan. major · TWSE:6239 · $2.4B rev · Taiwan
  • Chipbond Technology — Display-driver IC bumping, COG, and gold-bump packaging and test leader. major · TPEx:6147 · $677M rev · Taiwan
  • Unisem — Malaysian OSAT providing chip assembly and test services. major · KLSE:5005 · $460M rev · Malaysia
  • Sigurd Microelectronics — Taiwanese IC final-test and assembly provider. niche · TPEx:6257 · Taiwan
  • ChipMOS Technologies — OSAT focused on display driver and memory packaging/test. niche · TWSE:8150 · $755M rev · Taiwan
  • Greatek Electronics — Taiwanese OSAT specializing in memory and logic packaging. niche · TWSE:2441 · $503M rev · Taiwan
  • SFA Semicon — Korean OSAT, the former STS Semiconductor. niche · KOSDAQ:036540 · $271M rev · South Korea
  • Orient Semiconductor (OSE) — Taiwanese outsourced assembly and test provider. niche · TWSE:2329 · $526M rev · Taiwan
  • Nepes — Korean OSAT specializing in fan-out advanced packaging. niche · KOSDAQ:033640 · South Korea
  • LB Semicon — Korean OSAT focused on display driver packaging. niche · KOSDAQ:061970 · South Korea
  • Hana Micron — Korean OSAT serving Samsung and SK hynix memory packaging. niche · KRX:067310 · South Korea
  • Integra Technologies — US OSAT for high-reliability and defense applications. niche · United States
  • Lingsen Precision — Taiwanese outsourced assembly and test provider. niche · TWSE:3018 · Taiwan
  • UTAC Holdings — Singapore-based OSAT for analog and mixed-signal devices. niche · Singapore
  • Walton Advanced Engineering — Memory and logic packaging and test services. niche · TPEx:8110 · Taiwan

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Cite as: wafergraph, “Outsourced Assembly & Test companies — list, suppliers & market position”, https://wafergraph.com/segment/osat/assembly_test/ (data as of 2026-10-04).

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