Who owns Amkor (AMKR)?
105 holders named in SEC filings declare between 73.3% and 95.1% of Amkor's shares outstanding, as of Sep 22, 2026. The largest are John T. Kim (30.3%), Susan Y. Kim (17.0%) and Vanguard (6.9%); the five largest hold 63.6% together. Another 544 institutions hold small positions worth 3.8%. At least 1.1% of the shares appear in no ownership filing: investors who do not have to report, mostly individuals. From Mar 31, 2026 to Jun 30, 2026, institutions that filed both quarters bought 7.6% and sold 9.9% of the shares, a net sale of 2.3%; 157 opened a position, 205 added, 188 reduced and 46 sold out. Biggest buyers: Vanguard (+1.9M shares) and Clal Insurance Enterprises Holdings Ltd (+1.8M shares). Biggest sellers: Dimensional (-2.9M) and Jane Street (-2.0M). Directors and officers, from their latest Form 4: Susan Y. Kim (17.0%) and James J. Kim (4.5%). Over time, 633 managers declared Amkor in their 13F for Q2 2026, against 188 for Q4 2019: together at most 46.8% of the shares outstanding, against 39.2%.
| Holder | Filing | Share of capital | As of | Holding since (13F) |
|---|---|---|---|---|
| John T. Kim | 13D | 30.3% | May 1, 2026 | — |
| Susan Y. Kim | Form 4 | 17.0% | Sep 22, 2026 | — |
| Vanguard | 13F | 6.9% | Jun 30, 2026 | Q4 2019 or earlier |
| BlackRock | 13F | 4.9% | Jun 30, 2026 | Q4 2019 or earlier |
| James J. Kim | Form 4 | 4.5% | Jul 20, 2026 | — |
| Dimensional | 13F | 3.2% | Jun 30, 2026 | Q4 2019 or earlier |
| JPMorgan | 13F | 2.3% | Jun 30, 2026 | Q4 2019 or earlier |
| State Street | 13F | 1.5% | Jun 30, 2026 | Q4 2019 or earlier |
| AQR | 13F | 1.3% | Jun 30, 2026 | Q4 2019 or earlier |
| EARNEST PARTNERS LLC | 13F | 1.1% | Jun 30, 2026 | Q3 2022 |
| Geode Capital | 13F | 1.1% | Jun 30, 2026 | Q4 2019 or earlier |
| Invesco | 13F | 1.0% | Jun 30, 2026 | Q4 2019 or earlier |
| Point72 | 13F | 1.00% | Jun 30, 2026 | Q2 2025 |
| PRINCIPAL FINANCIAL GROUP INC | 13F | 0.79% | Jun 30, 2026 | Q1 2021 |
| FIRST TRUST ADVISORS LP | 13F | 0.74% | Jun 30, 2026 | Q4 2019 or earlier |
| Charles Schwab | 13F | 0.74% | Jun 30, 2026 | Q4 2019 or earlier |
| Fisher Asset Management, LLC | 13F | 0.73% | Jun 30, 2026 | Q4 2022 |
| Clal Insurance Enterprises Holdings Ltd | 13F | 0.71% | Jun 30, 2026 | Q2 2026 |
| T. Rowe Price | 13F | 0.67% | Jun 30, 2026 | Q4 2019 or earlier |
| Morgan Stanley | 13F | 0.61% | Jun 30, 2026 | Q4 2019 or earlier |
| Norges Bank | 13F | 0.59% | Jun 30, 2026 | Q4 2019 or earlier |
| Qube Research & Technologies Ltd | 13F | 0.47% | Jun 30, 2026 | Q4 2025 |
| Allianz Asset Management GmbH | 13F | 0.44% | Jun 30, 2026 | Q4 2019 or earlier |
| Two Sigma | 13F | 0.43% | Jun 30, 2026 | Q1 2022 |
| American Century Companies, Inc. | 13F | 0.42% | Jun 30, 2026 | Q4 2019 or earlier |
Amkor institutional ownership over time
| Quarter | 13F managers | Share of the company (upper bound) | Value declared | Held by stock pickers |
|---|---|---|---|---|
| Q4 2019 | 188 | 39.2% | $1.2B | 63.5% |
| Q4 2020 | 215 | 38.2% | $1.4B | 63.3% |
| Q4 2021 | 266 | 38.4% | $2.3B | 58.9% |
| Q4 2022 | 286 | 38.6% | $2.3B | 55.8% |
| Q4 2023 | 311 | 42.8% | $3.5B | 52.3% |
| Q4 2024 | 328 | 44.3% | $2.8B | 53.0% |
| Q4 2025 | 448 | 46.1% | $4.5B | 54.6% |
| Q2 2026 | 633 | 46.8% | $10.0B | 54.1% |
From SEC Form 13F, every quarter since the end of 2019, read like the current quarter: entities of a house summed, a value contradicting its share count set aside. The share of the company is an upper bound — two managers can declare the same shares — over the shares outstanding at that date.