COSTCO WHOLESALE CORP (COST) Institutional Ownership Changes & 13F Activity

COSTCO WHOLESALE CORP (COST) institutional ownership data tracks hedge funds, asset managers, and other institutional investors based on recent SEC 13F filings (Q1 2026). This page analyzes institutional buying and selling activity, new holdings, and sold-out positions among tracked filers. Notable filers include Renaissance Technologies LLC, Parnassus Endeavor Fund, Sequoia Financial Advisors, Greenbrier Partners Capital Management, and Alapocas Investment Partners.

Portfolio quarterNameTypeQuantityRemainingReported stock balance
Q4 2018Renaissance Technologies LLCBuy543,172722,185$147,116
Q4 2018Sequoia FundSell-17,2283,025$616
Q4 2018Ariel Appreciation FundSell-452137,560$28,022
Q4 2018Semper Augustus Investments GroupSell-30019,516$3,976
Q4 2018Sequoia Financial AdvisorsSell-411,592$324
Q3 2018Renaissance Technologies LLCSell-799,887179,013$42,047
Q3 2018Parnassus Endeavor FundSell-265,00025,000$5,872
Q3 2018Ariel Appreciation FundSell-91,970138,012$32,416
Q3 2018Sequoia FundSell-45620,253$4,757
Q3 2018Gardner Russo & QuinnSell-2465,227$1,228
Q3 2018Mairs & Power Growth FundSell-1503,522$827
Q3 2018Sequoia Financial AdvisorsBuy161,633$384
Q2 2018Parnassus Endeavor FundSell-60,000290,000$60,604
Q2 2018Greenbrier Partners Capital ManagementBuy25,000250,000$52,245
Q2 2018Ariel Appreciation FundBuy3,157229,982$48,062
Q2 2018Sequoia Financial AdvisorsSell-3661,617$338
Q2 2018Mairs & Power Growth FundBuy2003,672$767
Q2 2018Sequoia FundSell-9620,709$4,328
Q2 2018Semper Augustus Investments GroupSell-3519,816$4,141
Q1 2018Renaissance Technologies LLCSell-1,122,013978,900$184,454
Q1 2018Sequoia FundBuy20,80520,805$3,820
Q1 2018Ariel Appreciation FundSell-7,688226,825$42,741
Q1 2018Gardner Russo & QuinnBuy5,4735,473$1,031
Q1 2018Sequoia Financial AdvisorsBuy1,9831,983$374
Q1 2018Mairs & Power Growth FundBuy5963,472$654
Q1 2018Semper Augustus Investments GroupSell-40019,851$3,741
Q4 2017Renaissance Technologies LLCBuy890,2002,100,913$391,022
Q4 2017Ariel Appreciation FundBuy5,916234,513$43,648
Q4 2017Mairs & Power Growth FundSell-1262,876$535
Q3 2017Renaissance Technologies LLCSell-383,7871,210,713$198,908

Frequently asked questions about COST activity

  • Which institutional owners are buying COST?

    Institutional owners buying COST include investors who have either initiated new positions or increased their existing holdings based on recent SEC 13F filings. The activity table above highlights which funds added shares in the latest reporting periods and how their positions changed over time.

  • What does "buy" mean in COST activity?

    "Buy" means an investor increased their reported position in COST compared to the prior reporting period. This reflects growing exposure to COSTCO WHOLESALE CORP (COST) rather than necessarily a brand-new position (though new positions also appear as buys when prior quantity was zero).

  • Is institutional interest in COST increasing?

    Institutional interest in COST can be assessed by comparing the number of tracked funds adding or increasing positions versus those trimming or exiting across the periods shown. A higher number of additions typically signals increasing participation among large filers, but it should be read alongside position sizes and the full table.

Related COST insights