COST insider buying and SEC filings, explained
Costco Wholesale Corp. · CIK 909832
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)
$14.6M
Planned sales (10b5-1)
$0
Insider purchases and sales, last 12 months
| Traded | Type | What was filed | Source |
|---|---|---|---|
| Oct 13, 2026 | Sale | William Richard Wilcox (Executive Vice President) sold 1,100 shares at $958.21 ($1.1M). Holdings down 26% to 3,094 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Oct 14, 2026, 7:00 PM ET |
| Sep 29, 2026 | Sale | Caton Frates (Sr. Executive Vice President) sold 801 shares at $915.93 ($733K). Holdings down 9% to 7,912 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 30, 2026 |
| Sep 29, 2026 | Sale | Claudine Adamo (Executive Vice President) sold 2,200 shares at $915.93 ($2.0M). Holdings down 24% to 7,134 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 30, 2026 |
| Jun 23, 2026 | Sale | Kenneth D. Denman (Director) sold 885 shares at about $957.45 ($847K). Holdings down 16% to 4,779 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 25, 2026 |
| Apr 1, 2026 | Sale | Caton Frates (Executive Vice President) sold 700 shares at $993.00 ($695K). Holdings down 11% to 5,815 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Apr 1, 2026 |
| Mar 9, 2026 | Sale | Claudine Adamo (Executive Vice President) sold 730 shares at $1,003.02 ($732K). Holdings down 11% to 6,121 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Mar 11, 2026 |
| Jan 21, 2026 | Sale | Teresa A. Jones (Executive Vice President) sold 850 shares at about $986.26 ($838K). Holdings down 17% to 4,228 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jan 23, 2026 |
| Jan 16, 2026 | Sale | Susan L. Decker (Director) sold 458 shares at $955.00 ($437K). Holdings down 5% to 8,532 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jan 20, 2026 |
| Jan 14, 2026 | Sale | James C Klauer (Executive Vice President) sold 1,500 shares at $939.00 ($1.4M). Holdings down 3% to 44,837 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jan 15, 2026 |
| Jan 9, 2026 | Sale | Russell D Miller (Sr. Executive Vice President) sold 1,500 shares indirectly (by trust) at $916.32 ($1.4M). Holdings by trust down 15% to 8,240 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jan 12, 2026 |
| Dec 29–30, 2025 | Sale | Javier Polit (Executive Vice President) sold 2,607 shares between Dec 29, 2025 and Dec 30, 2025 at about $866.29 ($2.3M). Holdings down 20% to 10,190 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Dec 31, 2025 |
| Nov 7, 2025 | Sale | William Richard Wilcox (Executive Vice President) sold 2,400 shares at $930.13 ($2.2M). Holdings down 55% to 2,000 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Nov 12, 2025 |
34 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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