Jabil vs Amkor Technology: which stock is doing better?
Jabil and Amkor Technology are business rivals. Where they compete: outsourced semiconductor assembly and test (OSAT), adjacent contract manufacturing for electronics OEMs. Here is how the two stocks, and the businesses behind them, compare over the past year.
Updated Oct 9, 2026
JBL ahead
On Stox’s P3 score, which combines market beat, staying power and business growth, Jabil rates 70 and Amkor Technology 63. Over the past year Jabil is +48% and Amkor Technology +60%, against +16% for the S&P 500. Jabil has grown revenue faster, +19% against +13%. Jabil swings less, about 4.3% on a typical day against 6.6%. By type, Jabil is a Bellwether and Amkor Technology a Rolling Over.
The past year
JBL against AMKR, each set to $100 a year ago. Select a measure in the table below to chart it for both.
JBL and AMKR side by side
Ahead marks the stronger reading on each line; for the typical day and the deepest fall it marks the steadier stock. Select a row with a chart to see both over the year.
| Measure | JBL | AMKR | Ahead |
|---|---|---|---|
P3 score Market beat, staying power and business growth combined | 70Strong | 63Middling | JBL |
Past year Share price change | +48% | +60% | AMKR |
Past 3 months Share price change | −5% | −26% | JBL |
Past month Share price change | +1% | −1% | JBL |
Market beat Return against the market, past year | 91Strong | 94Strong | AMKR |
Staying power How steadily it has led, 52 weeks | 68Strong | 93Strong | AMKR |
Business growth Revenue, margins and cash flow growth | 55Middling | 28Weak | JBL |
Money flow Buying against selling on volume, 60 days | 81Strong | 22Weak | JBL |
Revenue growth Past four quarters against the year before | +19% | +13% | JBL |
Operating margin Operating profit as a share of revenue, past four quarters | 4% | 8% | AMKR |
Typical day Average daily move over the past year | 4.3% | 6.6% | JBL, calmer |
Deepest fall From a high, past year | −26% | −54% | JBL, held up |
Market value What the market values the company at | $32.1B | $12.2B | |
Type Its Stox Atlas type | Bellwether | Rolling Over | |
Group Stocks it moves with | Semis & hardware | Semis & hardware | Same group |
How to read this page
How it’s measured. Scores from Stox rank each stock against about 1,200 large US stocks and funds, where 100 is best; P3 combines market beat, staying power and business growth. Returns are share-price changes. The typical day is the average true range over 14 days as a share of the price, averaged over the past year.
Sources. Daily prices and company financial statements from Financial Modeling Prep; scores and curated rivals from Stox.
A higher score describes a stronger past year, not what comes next.
Rivals are chosen by the markets the two businesses compete in, not by sector labels.
For financial statements, valuation and news, see JBL and AMKR on Stox.
This page is information, not investment advice. About our data and methods ›