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COST Costco Wholesale Corp

Insider figures are trailing 90 days, open-market Form 4 only. Institutional figures are the latest reported quarter. These windows are not simultaneous.

-$847K net selling - trailing 90 days

0 buyers - 1 unique sellers

Historical context: No open-market activity in Aug 2026 — insiders sold in 14 of the last 23 months (limited history)

Institutional activity: not available - insufficient comparable institutions for the latest complete quarter.

open-market Form 4 only - grants, exercises, tax withholding excluded. ~ derived from SEC-reported shares x price.

Insider net $ (monthly)open-market Form 4 only - grants, exercises, tax withholding excluded$10.0M$5.0M$0-$5.0M-$10.0M2024-10 -$7.7M2024-11 $02024-12 $02025-01 $02025-02 $02025-03 -$6.0M2025-04 -$3.9M2025-05 $02025-06 -$5.6M2025-07 -$3.9M2025-08 -$595K2025-09 -$4.5M2025-10 -$3.7M2025-11 -$2.2M2025-12 -$2.3M2026-01 -$4.1M2026-02 $02026-03 -$732K2026-04 -$695K2026-05 $02026-06 -$847K2026-07 $02026-08 $0Oct 24Dec 24Feb 25Apr 25Jun 25Aug 25Oct 25Dec 25Feb 26Apr 26Jun 26Aug 26~ derived from SEC-reported shares x price. Hatched: excluded (implausible price) or unpriced.

Institutional activity: not available - insufficient comparable institutions for the latest complete quarter.

Who is responsible

Insider Role Net activity Rows
DENMAN KENNETH D -~$0.8M 1

Transactions

Date Insider Role Type Shares Price Value
6/23/2026 DENMAN KENNETH D S -885 957.4525 ~$0.8M
4/1/2026 Frates Caton Executive Vice President S -700 993 ~$0.7M
3/9/2026 Adamo Claudine Executive Vice President S -730 1003.021 ~$0.7M
1/21/2026 Jones Teresa A. Executive Vice President S -850 986.2567 ~$0.8M
1/16/2026 DECKER SUSAN L S -458 955 ~$0.4M
1/14/2026 Klauer James C Executive Vice President S -1500 939 ~$1.4M
1/9/2026 Miller Russell D Sr. Executive Vice President S -1500 916.32 ~$1.4M
12/30/2025 POLIT JAVIER Executive Vice President S -558.305 862.895 ~$0.5M
12/29/2025 POLIT JAVIER Executive Vice President S -2049 867.2054 ~$1.8M
11/7/2025 Wilcox William Richard Executive Vice President S -2400 930.13 ~$2.2M
10/24/2025 Adamo Claudine Executive Vice President S -2700 935.68 ~$2.5M
10/24/2025 Barbre Tiffany Marie S -1239.383 934.6204 ~$1.2M
9/29/2025 Frates Caton Executive Vice President S -1540 910.02 ~$1.4M
9/29/2025 Miller Russell D Sr. Executive Vice President S -3381 915 ~$3.1M
8/20/2025 Jones Teresa A. Executive Vice President S -600 992.05 ~$0.6M
7/14/2025 Rubanenko Yoram Executive Vice President S -4000 974.963 ~$3.9M
6/18/2025 DECKER SUSAN L 2 reported sale rows 547 ~$0.5M
6/9/2025 Callans Patrick J Executive Vice President S -3000 1002.766 ~$3.0M
6/6/2025 Riel Pierre Executive Vice President S -2000 1014.147 ~$2.0M
4/17/2025 Klauer James C Executive Vice President S -4000 981.07 ~$3.9M
3/27/2025 MILLERCHIP GARY Executive Vice President S -1100 940.006 ~$1.0M
3/24/2025 Adamo Claudine Executive Vice President S -900 922.56 ~$0.8M
3/18/2025 Frates Caton Executive Vice President S -850 900.2501 ~$0.8M
3/11/2025 Vachris Roland Michael President and CEO S -3600 931 ~$3.4M
10/24/2024 GALANTI RICHARD A Executive Vice President S -1416.461 894.6802 ~$1.3M
10/23/2024 Jones Teresa A. Executive Vice President S -800 896.545 ~$0.7M
10/15/2024 Riel Pierre Executive Vice President S -2000 896.713 ~$1.8M
10/11/2024 Miller Russell D Sr. Executive Vice President S -4400 891.152 ~$3.9M
9/30/2024 Frates Caton Executive Vice President S -1700 883.35 ~$1.5M
9/30/2024 Adamo Claudine Executive Vice President S -3200 888.993 ~$2.8M
9/30/2024 Callans Patrick J Executive Vice President S -2500 893.94 ~$2.2M