FORM insider buying and SEC filings, explained
Formfactor Inc. · CIK 1039399
Tracked: Forms 3/4/5, 8-K, NT · All filings on sec.gov
Insider activity in the last 12 months
Bought
$0
Insiders who bought
0
Sold (not marked 10b5-1)
$6.9M
Planned sales (10b5-1)
$16.5M
Insider purchases and sales, last 12 months
| Traded | Type | What was filed | Source |
|---|---|---|---|
| Oct 14, 2026 | Planned (10b5-1) | Mike Slessor (CEO and Director) sold 11,098 shares at about $125.20 ($1.4M), marked as a 10b5-1 plan trade. Holdings down 2% to 455,596 shares. | SEC filing Filed Oct 14, 2026, 8:06 PM ET |
| Sep 16, 2026 | Planned (10b5-1) | Mike Slessor (CEO and Director) sold 17,510 shares at about $104.73 ($1.8M), marked as a 10b5-1 plan trade. Holdings down 4% to 466,694 shares. | SEC filing Filed Sep 17, 2026 |
| Sep 3, 2026 | Sale | Kelley Steven-Waiss (Director) sold 2,100 shares at $96.10 ($202K). Holdings down 8% to 24,426 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 4, 2026 |
| Aug 14, 2026 | Planned (10b5-1) | Mike Slessor (CEO and Director) sold 16,002 shares at about $130.95 ($2.1M), marked as a 10b5-1 plan trade. Holdings down 3% to 484,204 shares. | SEC filing Filed Aug 17, 2026 |
| Jul 15, 2026 | Planned (10b5-1) | Mike Slessor (CEO and Director) sold 4,735 shares at about $118.31 ($560K), marked as a 10b5-1 plan trade. Holdings down 1% to 430,412 shares. | SEC filing Filed Jul 16, 2026 |
| Jun 15, 2026 | Sale | Dennis Thomas St (Director) sold 2,800 shares at $151.49 ($424K). Holdings down 9% to 29,073 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 16, 2026 |
| Jun 10, 2026 | Planned (10b5-1) | Mike Slessor (CEO and Director) sold 11,890 shares at about $121.35 ($1.4M), marked as a 10b5-1 plan trade. Holdings down 3% to 435,147 shares. | SEC filing Filed Jun 11, 2026 |
| Jun 2, 2026 | Sale | Sheri Rhodes (Director) sold 6,328 shares at $125.40 ($794K). Holdings down 54% to 5,375 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 4, 2026 |
| May 21, 2026 | Sale | Rebeca Obregon-Jimenez (Director) sold 3,828 shares at $126.48 ($484K). Holdings down 33% to 7,875 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed May 22, 2026 |
| May 20, 2026 | Sale | Brian C. White (Director) sold 3,250 shares at $126.00 ($410K). Holdings down 27% to 8,653 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed May 21, 2026 |
| May 19, 2026 | Sale | Dennis Thomas St (Director) sold 1,000 shares at about $115.84 ($116K). Holdings down 3% to 31,873 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed May 21, 2026 |
| May 15, 2026 | Sale | Kelley Steven-Waiss (Director) sold 5,400 shares at $125.60 ($678K). Holdings down 18% to 25,179 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed May 15, 2026 |
| May 13, 2026 | Sale | Jorge Titinger (Director) sold 4,009 shares at $128.79 ($516K). Holdings down 23% to 13,489 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed May 15, 2026 |
| May 13, 2026 | Planned (10b5-1) | Mike Slessor (CEO and Director) sold 9,438 shares at about $126.52 ($1.2M), marked as a 10b5-1 plan trade. Holdings down 2% to 447,037 shares. | SEC filing Filed May 14, 2026 |
| Apr 15, 2026 | Planned (10b5-1) | Mike Slessor (CEO and Director) sold 11,294 shares at about $127.72 ($1.4M), marked as a 10b5-1 plan trade. Holdings down 2% to 449,565 shares. | SEC filing Filed Apr 15, 2026 |
| Mar 18, 2026 | Planned (10b5-1) | Mike Slessor (CEO and Director) sold 10,227 shares at about $95.15 ($973K), marked as a 10b5-1 plan trade. Holdings down 2% to 460,859 shares. | SEC filing Filed Mar 18, 2026 |
| Mar 5, 2026 | Planned (10b5-1) | Aric Brendan McKinnis (CFO) sold 3,462 shares at $90.42 ($313K), marked as a 10b5-1 plan trade. Holdings down 24% to 11,140 shares. | SEC filing Filed Mar 6, 2026 |
| Feb 24, 2026 | Sale | Brian C. White (Director) sold 2,300 shares at $100.01 ($230K). Holdings down 18% to 10,556 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 25, 2026 |
| Feb 18, 2026 | Planned (10b5-1) | Mike Slessor (CEO and Director) sold 8,664 shares at about $94.14 ($816K), marked as a 10b5-1 plan trade. Holdings down 2% to 471,086 shares. | SEC filing Filed Feb 18, 2026 |
| Feb 11, 2026 | Sale | Kevin J. Brewer (Director) sold 3,000 shares at $96.20 ($289K). Holdings down 27% to 8,105 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 12, 2026 |
| Feb 10, 2026 | Sale | Dennis Thomas St (Director) sold 7,431 shares at about $93.84 ($697K). Holdings down 19% to 31,526 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 11, 2026 |
| Feb 10, 2026 | Sale | Sheri Rhodes (Director) sold 7,634 shares at $92.61 ($707K). Holdings down 42% to 10,356 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 11, 2026 |
| Feb 10, 2026 | Sale | Kelley Steven-Waiss (Director) sold 2,200 shares at $93.70 ($206K). Holdings down 7% to 30,579 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 11, 2026 |
| Feb 9, 2026 | Sale | Rebeca Obregon-Jimenez (Director) sold 2,770 shares at $95.82 ($265K). Holdings down 21% to 10,356 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 10, 2026 |
| Feb 9, 2026 | Sale | Brian C. White (Director) sold 5,500 shares at $90.95 ($500K). Holdings down 30% to 12,856 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 10, 2026 |
| Feb 9, 2026 | Sale | Jorge Titinger (Director) sold 2,000 shares at $88.84 ($178K). Holdings down 10% to 17,498 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Feb 10, 2026 |
| Jan 15, 2026 | Planned (10b5-1) | Mike Slessor (CEO and Director) sold 13,088 shares at about $76.81 ($1.0M), marked as a 10b5-1 plan trade. Holdings down 3% to 472,907 shares. | SEC filing Filed Jan 15, 2026 |
| Jan 6, 2026 | Planned (10b5-1) | Mike Slessor (CEO and Director) sold 39,606 shares at $65.00 ($2.6M), marked as a 10b5-1 plan trade. Holdings down 8% to 485,995 shares. | SEC filing Filed Jan 6, 2026 |
| Dec 17, 2025 | Planned (10b5-1) | Mike Slessor (CEO and Director) sold 7,669 shares at about $56.36 ($432K), marked as a 10b5-1 plan trade. Holdings down 1% to 525,601 shares. | SEC filing Filed Dec 17, 2025 |
| Dec 2, 2025 | Sale | Kelley Steven-Waiss (Director) sold 2,700 shares at $55.97 ($151K). Holdings down 8% to 32,779 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Dec 2, 2025 |
| Nov 19, 2025 | Planned (10b5-1) | Mike Slessor (CEO and Director) sold 8,403 shares at about $50.06 ($421K), marked as a 10b5-1 plan trade. Holdings down 2% to 533,270 shares. | SEC filing Filed Nov 19, 2025 |
| Nov 17, 2025 | Sale | Dennis Thomas St (Director) sold 2,000 shares at $49.85 ($100K). Holdings down 5% to 38,957 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Nov 17, 2025 |
25 routine transactions (such as grants, option exercises or tax withholding) are not listed.
Cluster buys
No cluster buys in the last 12 months.
Red flags
No red flags in the last 12 months.
Key events
No key events in the last 12 months.
8-K filings, last 12 months
No 8-K filings in the last 12 months.
Red flags are objective triggers only: the item or form filed, never an opinion.
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