Ernest E. Maddock is CFO at LAM RESEARCH CORP (LRCX). They have made 14 open-market trades across 6 companies since 2010, most recently 2026-06-17.
CIK 0001227050
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.
11 open-market purchases totalling $974K since 2015, against 3 sales. Across 11 scored buys the stock is up 0.6% at ninety days, and 3.0 points behind the S&P over the same stretch.
11 scored purchases · one row per filing · discretionary only
| 7d | 30d | 90d | |
|---|---|---|---|
| Accuracy | 45% | 64% | 45% |
| Avg Move | -1.7% | -2.1% | +0.6% |
| Alpha | -1.7% | -2.7% | -3.0% |
| Scored | 11 | 11 | 11 |
| Ticker | Type | Traded | Filed | Price | Value | 7d Stock | 30d Stock | 90d Stock |
|---|---|---|---|---|---|---|---|---|
| UCTT | BUY | 2025-03-07 | 2025-03-11 | $24.29 | $243K | -2.4% | -20.7% | -14.1% |
| OUST | BUY | 2024-08-16 | 2024-08-19 | $7.79 | $62K | -11.8% | -25.9% | +8.1% |
| TER | BUY | 2024-02-01 | 2024-02-05 | $94.07 | $94K | +6.1% | +10.4% | +26.2% |
| OUST | BUY | 2023-11-15 | 2023-11-16 | $5.29 | $37K | +1.2% | +27.5% | +11.7% |
| OUST | BUY | 2023-08-21 | 2023-08-22 | $6.02 | $42K | -1.4% | -16.5% | -5.5% |
| VLDR | BUY | 2022-03-04 | 2022-03-08 | $2.50 | $50K | +11.9% | +3.7% | -23.4% |
| UCTT | BUY | 2018-07-31 | 2018-08-02 | $13.40 | $13K | -4.2% | +3.1% | -26.5% |
| MU | BUY | 2017-08-11 | 2017-08-15 | $27.89 | $95K | +0.9% | +15.2% | +51.9% |
| MU | BUY | 2016-01-21 | 2016-01-25 | $10.69 | $107K | +6.4% | +0.9% | +0.0% |
| MU | BUY | 2015-12-24 | 2015-12-28 | $14.32 | $143K | -12.8% | -24.9% | -24.9% |
| MU | BUY | 2015-07-09 | 2015-07-10 | $17.50 | $88K | -12.8% | +3.6% | +3.6% |
| LRCX | SELL | 2013-02-05 | 2013-02-07 | $42.28 | $509K | -11.2% | -0.1% | -0.1% |
| LRCX | SELL | 2013-01-28 | 2013-01-30 | $41.69 | $519K | -11.2% | -0.1% | -0.1% |
| LRCX | SELL | 2011-03-02 | 2011-03-04 | $56.65 | $1.4M | -11.2% | -0.1% | -0.1% |
| LRCX | SELL · 10b5-1 | 2010-12-07 | 2010-12-08 | $50.00 | $153K | -11.2% | -0.1% | -0.1% |
Grouped by shared companies and similar filing behaviour. This is a similarity measure, not a ranking or a performance signal.
| ISIL |
| 8,828 |
| $199K |
| RVBD | 205,143 | — |
| Total | $208.2M |
Shares reported on the most recent Form 4, priced at the 2026-06-22 close. 1 holding could not be priced and is excluded from the total.