Amkor Technology, Inc.
MX ˙ BMV ˙ US0316521006
SecurityMX:AMKR / Amkor Technology, Inc.
InstitutionBandera Partners LLC
Latest Disclosed Ownership693,519 shares
Latest Disclosed Value $ 31,229,161
Bandera Partners LLC ownership in AMKR / Amkor Technology, Inc.

On May 13, 2026 - Bandera Partners LLC filed a 13F-HR form disclosing ownership of 693,519 shares of Amkor Technology, Inc. (MX:AMKR) valued at $31,229,161 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 693,519 shares of Amkor Technology, Inc.. This represents a change in shares of 0.00% during the quarter.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

Upgrade to unlock premium data and export to Excel .

Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-13 2026-03-31 13F AMKOR TECHNOLOGY COM 031652100 693,519 0 0.00 31,229 14.06 14.1251
2026-02-13 2025-12-31 13F AMKOR TECHNOLOGY COM 031652100 693,519 -79,974 -10.34 27,380 24.64 12.3069
2025-11-12 2025-09-30 13F AMKOR TECHNOLOGY COM 031652100 773,493 0 0.00 21,967 35.31 9.6293
2025-08-12 2025-06-30 13F AMKOR TECHNOLOGY COM 031652100 773,493 468,640 153.73 16,236 194.91 7.3178
2025-05-13 2025-03-31 13F AMKOR TECHNOLOGY COM 031652100 304,853 0 0.00 5,506 -29.70 1.9809
2025-02-12 2024-12-31 13F AMKOR TECHNOLOGY COM 031652100 304,853 0 0.00 7,832 -16.05 2.9817
2024-11-12 2024-09-30 13F AMKOR TECHNOLOGY COM 031652100 304,853 0 0.00 9,329 -23.54 3.5213
2024-08-12 2024-06-30 13F AMKOR TECHNOLOGY COM 031652100 304,853 0 0.00 12,200 24.14 4.4226
2024-05-14 2024-03-31 13F AMKOR TECHNOLOGY COM 031652100 304,853 0 0.00 9,828 -3.10 3.8305
2024-02-13 2023-12-31 13F AMKOR TECHNOLOGY COM 031652100 304,853 -300,000 -49.60 10,142 -25.80 3.3592
2023-11-13 2023-09-30 13F AMKOR TECHNOLOGY COM 031652100 604,853 -10 -0.00 13,670 -24.04 4.9356
2023-08-10 2023-06-30 13F AMKOR TECHNOLOGY COM 031652100 604,863 -1,223,058 -66.91 17,995 -62.17 7.6404
2023-05-12 2023-03-31 13F AMKOR TECHNOLOGY COM 031652100 1,827,921 0 0.00 47,563 8.51 19.5632
2023-02-13 2022-12-31 13F AMKOR TECHNOLOGY COM 031652100 1,827,921 0 0.00 43,834 40.64 20.7466
2022-11-10 2022-09-30 13F AMKOR TECHNOLOGY COM 031652100 1,827,921 0 0.00 31,166 0.59 13.0629
2022-08-12 2022-06-30 13F AMKOR TECHNOLOGY COM 031652100 1,827,921 113,172 6.60 30,983 -16.81 12.1906
2022-05-13 2022-03-31 13F AMKOR TECHNOLOGY COM 031652100 1,714,749 134,749 8.53 37,244 -4.91 11.0889
2022-02-14 2021-12-31 13F AMKOR TECHNOLOGY COM 031652100 1,580,000 0 0.00 39,168 -0.64 14.0034
2021-11-12 2021-09-30 13F AMKOR TECHNOLOGY COM 031652100 1,580,000 761,450 93.02 39,421 103.46 15.8963
2021-08-13 2021-06-30 13F AMKOR TECHNOLOGY COM 031652100 818,550 148,813 22.22 19,375 22.02 7.5909
2021-05-27 2021-03-31 13F/A-1 AMKOR TECHNOLOGY COM 031652100 669,737 669,737 15,879 6.2416
2021-05-14 2021-03-31 13F AMKOR TECHNOLOGY COM 031652100 669,737 669,737 15,879 6.2651
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.