John Z. Zhang is VP at CORNING INC /NY (GLW). They have made 17 open-market trades across 1 company since 2021, most recently 2026-05-11.
CIK 0001825618
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.
0 open-market purchases, against 17 sales. Too few scored purchases to measure a record yet.
| Ticker | Shares | Value |
|---|---|---|
| GLW | 5,138 | $678K |
Shares reported on the most recent Form 4, priced at the 2026-05-12 close.
Counted per filing, not per execution lot — a purchase filled in several tranches is one decision.
| Ticker | Type | Traded | Filed | Price | Value | 7d Stock | 30d Stock | 90d Stock |
|---|---|---|---|---|---|---|---|---|
| GLW | SELL | 2026-05-11 | 2026-05-12 | $198.34 | $2.0M | -6.8% | -15.0% | -24.1% |
| GLW | SELL | 2026-05-06 | 2026-05-06 | $184.67 | $2.8M | -3.7% | -4.3% | -13.7% |
| GLW | SELL | 2026-02-12 | 2026-02-12 | $133.75 | $205K | +23.0% | +1.3% | +58.4% |
| GLW | SELL | 2025-08-12 | 2025-08-12 | $65.53 | $159K | -0.4% | +14.3% | +34.1% |
| GLW | SELL | 2025-05-28 | 2025-05-29 | $49.29 | $947K | +2.6% | +6.6% | +36.3% |
| GLW | SELL | 2025-05-12 | 2025-05-13 | $46.91 | $375K | +1.3% | +6.5% | +36.1% |
| GLW | SELL | 2025-02-18 | 2025-02-19 | $52.78 | $1.5M | -8.0% | -7.5% | -8.5% |
| GLW | SELL | 2024-11-13 | 2024-11-14 | $48.36 | $250K | +3.0% | +3.4% | +11.7% |
| GLW | SELL | 2024-08-13 | 2024-08-15 | $39.73 | $1.0M | +5.8% | +6.7% | +17.4% |
| GLW | SELL | 2024-05-02 | 2024-05-02 | $33.42 | $839K | +3.5% | +10.7% | +18.5% |
| GLW | SELL | 2024-02-15 | 2024-02-16 | $32.02 | $423K | +1.9% | +2.2% | +11.3% |
| GLW | SELL | 2023-05-05 | 2023-05-09 | $31.45 | $472K | -0.4% | +0.8% | +5.3% |
| GLW | SELL | 2023-02-16 | 2023-02-17 | $35.52 | $408K | -1.7% | -5.3% | -10.9% |
| GLW | SELL | 2023-02-03 | 2023-02-06 | $36.00 | $168K | +1.6% | -1.2% | -9.6% |
| GLW | SELL | 2022-02-04 | 2022-02-04 | $42.01 | $1.1M | -0.7% | -12.6% | -14.4% |
| GLW | SELL | 2021-05-03 | 2021-05-05 | $44.62 | $1.6M | -2.5% | -4.2% | -8.0% |
| GLW | SELL | 2021-03-01 | 2021-03-02 | $39.23 | $895K | +5.5% | +13.9% | +11.6% |
Grouped by shared companies and similar filing behaviour. This is a similarity measure, not a ranking or a performance signal.