Costco Wholesale Corporation
MX ˙ BMV ˙ US22160K1051
SecurityMX:COST / Costco Wholesale Corporation
InstitutionCornerstone Advisors, LLC
Latest Disclosed Ownership39,204 shares
Latest Disclosed Value $ 39,064,042
Cornerstone Advisors, LLC reports 19.89% increase in ownership of COST / Costco Wholesale Corporation

On May 8, 2026 - Cornerstone Advisors, LLC filed a 13F-HR form disclosing ownership of 39,204 shares of Costco Wholesale Corporation (MX:COST) valued at $39,064,042 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 32,700 shares of Costco Wholesale Corporation. This represents a change in shares of 19.89% during the quarter.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-08 2026-03-31 13F COSTCO WHOLESALE COM 22160K105 39,204 6,504 19.89 39,064 38.53 1.4371
2026-02-13 2025-12-31 13F COSTCO WHSL CORP COM 22160K105 32,700 3,000 10.10 28,199 2.57 0.9389
2025-11-07 2025-09-30 13F COSTCO WHSL CORP COM 22160K105 29,700 0 0.00 27,491 -6.50 0.9064
2025-08-08 2025-06-30 13F COSTCO WHSL CORP COM 22160K105 29,700 300 1.02 29,401 5.74 1.0099
2025-05-09 2025-03-31 13F COSTCO WHSL CORP COM 22160K105 29,400 0 0.00 27,806 3.22 1.1978
2025-02-07 2024-12-31 13F COSTCO WHSL CORP COM 22160K105 29,400 200 0.68 26,938 4.06 1.0737
2024-11-08 2024-09-30 13F COSTCO WHSL CORP COM 22160K105 29,200 400 1.39 25,886 5.75 1.0235
2024-08-09 2024-06-30 13F COSTCO WHSL CORP COM 22160K105 28,800 -100 -0.35 24,480 15.61 0.9942
2024-05-10 2024-03-31 13F COSTCO WHSL CORP COM 22160K105 28,900 -4,100 -12.42 21,173 -2.80 0.8766
2024-02-09 2023-12-31 13F COSTCO WHSL CORP COM 22160K105 33,000 -4,500 -12.00 21,783 2.81 0.9584
2023-11-09 2023-09-30 13F COSTCO WHSL CORP COM 22160K105 37,500 -13,600 -26.61 21,186 -22.99 0.9873
2023-08-11 2023-06-30 13F COSTCO WHSL CORP COM 22160K105 51,100 -9,600 -15.82 27,511 -8.78 1.3127
2023-05-15 2023-03-31 13F COSTCO WHSL CORP COM 22160K105 60,700 0 0.00 30,160 8.85 1.3992
2023-02-14 2022-12-31 13F COSTCO WHSL CORP COM 22160K105 60,700 0 0.00 27,710 -3.34 1.3680
2022-11-10 2022-09-30 13F COSTCO WHOLESALE Common 22160K105 60,700 0 0.00 28,667 -1.46 1.4079
2022-08-12 2022-06-30 13F COSTCO WHOLESALE Common 22160K105 60,700 21,200 53.67 29,092 27.90 1.5260
2022-05-12 2022-03-31 13F COSTCO WHOLESALE Common 22160K105 39,500 0 0.00 22,746 1.44 1.3401
2022-05-11 2021-12-31 13F COSTCO WHOLESALE Common 22160K105 39,500 0 0.00 22,424 26.34 1.2182
2021-11-12 2021-09-30 13F COSTCO WHOLESALE Common 22160K105 39,500 0 0.00 17,749 13.56 1.0292
2021-08-13 2021-06-30 13F COSTCO WHOLESALE Common 22160K105 39,500 0 0.00 15,629 12.25 0.9224
2021-05-13 2021-03-31 13F COSTCO WHOLESALE Common 22160K105 39,500 0 0.00 13,923 -6.45 1.2195
2021-02-11 2020-12-31 13F COSTCO WHOLESALE Common 22160K105 39,500 0 0.00 14,883 6.13 1.3060
2020-11-13 2020-09-30 13F COSTCO WHOLESALE Common 22160K105 39,500 0 0.00 14,023 17.08 1.2586
2020-08-11 2020-06-30 13F COSTCO WHOLESALE Common 22160K105 39,500 0 0.00 11,977 6.34 1.1178
2020-05-13 2020-03-31 13F COSTCO WHOLESALE Common 22160K105 39,500 0 0.00 11,263 -2.99 1.2438
2020-02-12 2019-12-31 13F COSTCO WHOLESALE Common 22160K105 39,500 39,500 11,610 0.9561
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.