COSTCO WHOLESALE CORP (COST) Institutional Ownership and Insiders Activity

COSTCO WHOLESALE CORP (COST) is widely held by institutional investors, with 11 tracked firms reporting positions valued at approximately $1.03B based on SEC Form 13F filings for the quarter ended March 31, 2026.

Parnassus Endeavor Fund is the largest disclosed holder, reporting approximately $673.09M in COST holdings in its latest filing.

Institutional ownership among tracked investors remains highly concentrated, with Parnassus Endeavor Fund representing the majority of disclosed value.

Recent insider activity includes 1 tracked Form 4 transaction over the last three months, reflecting ongoing executive and director trading activity.