David C. Chang is Director at AXT INC (AXTI). They have made 14 open-market trades across 1 company since 2006, most recently 2026-06-15.
CIK 0001188184
Unrated. We grade insiders only on stock they chose to buy on the open market. Grants, option exercises and vesting say nothing about timing, so they don't count — which is why someone can file often and still have no grade. It isn't a bad sign: unrated buys beat every graded tier below A.
5 open-market purchases totalling $55K since 2006, against 9 sales. Across 5 scored buys the stock is up 6.5% at ninety days, and 6.3 points ahead of the S&P over the same stretch.
5 scored purchases · one row per filing · discretionary only
| Ticker | Shares | Value |
|---|---|---|
| AXTI | 65,165 | $3.4M |
| TWC | 4,678 | $980K |
| FJC | 56,284 | — |
| Total | $4.3M |
Shares reported on the most recent Form 4, priced at the 2026-06-17 close. 1 holding could not be priced and is excluded from the total.
Counted per filing, not per execution lot — a purchase filled in several tranches is one decision.
| 7d | 30d | 90d | |
|---|---|---|---|
| Accuracy | 0% | 100% | 100% |
| Avg Move | -2.0% | +6.5% | +6.5% |
| Alpha | +3.8% | +6.3% | +6.3% |
| Scored | 5 | 5 | 5 |
| Ticker | Type | Traded | Filed | Price | Value | 7d Stock | 30d Stock | 90d Stock |
|---|---|---|---|---|---|---|---|---|
| AXTI | SELL | 2026-06-15 | 2026-06-17 | $111.17 | $926K | -25.0% | -52.3% | -40.1% |
| AXTI | SELL | 2026-03-10 | 2026-03-12 | $46.00 | $920K | +45.6% | +41.4% | +81.2% |
| AXTI | SELL | 2026-03-04 | 2026-03-05 | $38.48 | $1.5M | +21.5% | +15.0% | +192.3% |
| AXTI | SELL | 2025-12-09 | 2025-12-10 | $14.84 | $371K | -1.0% | +49.6% | +188.2% |
| AXTI | SELL | 2025-11-28 | 2025-12-02 | $11.53 | $576K | +26.9% | +43.6% | +296.9% |
| AXTI | SELL | 2025-11-05 | 2025-11-06 | $8.94 | $894K | +17.4% | +50.8% | +122.4% |
| AXTI | SELL | 2020-05-28 | 2020-06-01 | $5.48 | $70K | -11.6% | -15.2% | +5.8% |
| AXTI | SELL | 2017-08-01 | 2017-08-02 | $8.80 | $79K | -9.9% | -7.0% | +8.1% |
| AXTI | SELL | 2010-11-23 | 2010-11-23 | $8.15 | $473K | -2.0% | +6.5% | +6.5% |
| AXTI | BUY | 2010-08-31 | 2010-08-31 | $5.15 | $15K | -2.0% | +6.5% | +6.5% |
| AXTI | BUY | 2010-08-23 | 2010-08-24 | $5.49 | $16K | -2.0% | +6.5% | +6.5% |
| AXTI | BUY | 2009-08-31 | 2009-09-01 | $1.81 | $5K | -2.0% | +6.5% | +6.5% |
| AXTI | BUY | 2006-08-21 | 2006-08-29 | $3.18 | $10K | -2.0% | +6.5% | +6.5% |
| AXTI | BUY | 2006-02-24 | 2006-03-10 | $2.97 | $8K | -2.0% | +6.5% | +6.5% |
Grouped by shared companies and similar filing behaviour. This is a similarity measure, not a ranking or a performance signal.