John D. Duke is CEO at HARVARD BIOSCIENCE INC (HBIO). They have made 1 open-market trade across 1 company since 2026, most recently 2026-03-20.
CIK 0002071593
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.
1 open-market purchase totalling $25K since 2026, never a sale. Too few scored purchases to measure a record yet.
| Ticker | Shares | Value |
|---|---|---|
| HBIO | 180,000 | $1.5M |
Shares reported on the most recent Form 4, priced at the 2026-03-23 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 |
|---|---|---|---|---|---|---|---|---|
| HBIO | BUY | 2026-03-16 | 2026-03-17 | $5.01 | $25K | -1.6% | +19.4% | +27.5% |
Grouped by shared companies and similar filing behaviour. This is a similarity measure, not a ranking or a performance signal.