Company · Ownership research

COSTCO WHOLESALE CORP /NEW COST

CIK 0000909832

Form 4 transactions dated Sep 1, 2023 to Sep 24, 2026, as reported to the SEC.

Insider trading Initial holdings Institutional holders

Insider filings on file run through 2026-07-14.

Insider purchases & sales

Purchased: $0.00
Sold: $83.08M

Sep 1, 2023 – Jul 14, 2026
Available records · partial months are marked ·

20267 of 7 preview events

Date	Insider	Activity	Trade value (USD)	% of prior holding
2026-06-23	DENMAN KENNETH D Director	Sale	$847.35K 885 shares sold	15.63% sold Direct holding	▾
2026-04-01	Frates Caton Executive Vice President	Sale	$695.10K 700 shares sold	10.74% sold Direct holding	▾
2026-03-09	Adamo Claudine Executive Vice President	Sale	$732.21K 730 shares sold	10.66% sold Direct holding	▾
2026-01-21	Jones Teresa A. Executive Vice President	Sale	$838.32K 850 shares sold	16.74% sold Direct holding	▾
2026-01-16	DECKER SUSAN L Director	Sale	$437.39K 458 shares sold	5.09% sold Direct holding	▾
2026-01-14	Klauer James C Executive Vice President	Sale	$1.41M 1,500 shares sold	3.24% sold Direct holding	▾
2026-01-09	Miller Russell D Sr. Executive Vice President	Sale	$1.37M 1,500 shares sold	15.40% sold Trust holding	▾

Showing 7 / 7 record groups in 2026. The complete set is available through the API.

COSTCO WHOLESALE CORP /NEW · COST

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The initial HTML of this page carries its exact data as script#research-data (JSON): values, units, scope, preview limits and SEC sources. Read it directly, no script or API key needed; script#research-access says what needs an account. For the year shown, this page lists 7 of 7 purchase / sale groups and 6 of 6 other groups; the totals and the monthly series cover the whole window.

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{"ticker":"COST","transaction_code":["P","S"],"transaction_form_type":"4","page_size":20}

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Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.

Non-cancelled, non-derivative purchase (P) and sale (S) rows dated inside the public window, as reported. Includes open-market and private transactions. Data after the latest filing is not asserted complete and is not zero-filled. A grouped event shares filing, transaction date, security, code, direction, ownership bucket and source. Derivative groups also match underlying security, exercise price, exercise/expiration dates and footnote references. Reported rows are retained; P/S price lots can be grouped. Post-transaction balances are never summed.