COSTCO WHOLESALE CORP (COST) Stock Institutional Trading Activity


COSTCO WHOLESALE CORP (COST) position changes reported by tracked institutional filers across multiple SEC 13F reporting periods. Based on recent SEC 13F filings (Q4 2025), investors with some of the largest reported share count changes include Renaissance Technologies LLC, Mairs & Power Growth Fund, Semper Augustus Investments Group, Matrix Advisors Value Fund, and Parnassus Endeavor Fund. Explore insights into buying and selling patterns, position changes, and investment conviction levels to understand institutional trading behavior and market dynamics.

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Portfolio quarterNameTypeQuantityRemainingReported stock balance
Q4 2016Renaissance Technologies LLCBuy733,5002,819,713$451,464
Q3 2016Mairs & Power Growth FundBuy3413,239$494
Q3 2016Ariel Appreciation FundBuy37,69775,667$11,540
Q3 2016Renaissance Technologies LLCBuy1,748,5132,086,213$318,168
Q2 2016Ariel Appreciation FundBuy23,13637,970$5,963
Q2 2016Renaissance Technologies LLCSell-772,513337,700$53,032
Q1 2016Ariel Appreciation FundBuy77114,834$2,338
Q1 2016Renaissance Technologies LLCBuy514,2131,110,213$174,947
Q4 2015Mairs & Power Growth FundSell-2402,898$468
Q4 2015Renaissance Technologies LLCSell-53,400596,000$96,254
Q3 2015Mairs & Power Growth FundBuy3403,138$454
Q3 2015Ariel Appreciation FundBuy10,35714,063$2,033
Q3 2015Semper Augustus Investments GroupSell-10020,302$2,935
Q3 2015Renaissance Technologies LLCSell-511,539649,400$93,884
Q2 2015Mairs & Power Growth FundBuy1572,798$378
Q2 2015Ariel Appreciation FundBuy2063,706$501
Q2 2015Renaissance Technologies LLCSell-34,0611,160,939$156,796
Q2 2015Greenbrier Partners Capital ManagementBuy25,000225,000$30,389
Q1 2015Ariel Appreciation FundBuy1113,500$530
Q1 2015Renaissance Technologies LLCSell-760,2131,195,000$181,037
Q1 2015Greenbrier Partners Capital ManagementBuy15,512200,000$30,299
Q4 2014Mairs & Power Growth FundBuy4502,641$374
Q4 2014Ariel Appreciation FundSell-1,8323,389$480
Q4 2014Semper Augustus Investments GroupSell-10020,402$2,892
Q4 2014Renaissance Technologies LLCBuy400,3001,955,213$277,151
Q3 2014Mairs & Power Growth FundSell-752,191$275
Q3 2014Ariel Appreciation FundBuy1645,221$654
Q3 2014Greenbrier Partners Capital ManagementSell-15,512184,488$23,120
Q3 2014Renaissance Technologies LLCBuy504,0131,554,913$194,862
Q2 2014Mairs & Power Growth FundSell-2482,266$261

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.