Costco Wholesale Corporation
MX ˙ BMV ˙ US22160K1051
SecurityMX:COST / Costco Wholesale Corporation
InstitutionGM Advisory Group, Inc.
Latest Disclosed Ownership5,934 shares
Latest Disclosed Value $ 5,912,814
GM Advisory Group, Inc. reports 6.89% decrease in ownership of COST / Costco Wholesale Corporation

On April 28, 2026 - GM Advisory Group, Inc. filed a 13F-HR form disclosing ownership of 5,934 shares of Costco Wholesale Corporation (MX:COST) valued at $5,912,814 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 6,373 shares of Costco Wholesale Corporation. This represents a change in shares of -6.89% 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)
2026-04-28 2026-03-31 13F Costco Wholesale CRP Del Com 22160K105 5,934 -439 -6.89 5,913 7.59 0.2187
2026-02-13 2025-12-31 13F Costco Wholesale CRP Del COM 22160K105 6,373 1,098 20.82 5,496 12.56 0.2153
2025-11-19 2025-09-30 13F COSTCO WHSL CORP COM 22160K105 5,275 165 3.23 4,883 -3.48 0.2076
2025-08-13 2025-06-30 13F COSTCO WHSL CORP COM 22160K105 5,110 1,392 37.44 5,058 43.86 0.2500
2025-05-14 2025-03-31 13F COSTCO WHSL CORP COM 22160K105 3,718 39 1.06 3,517 4.30 0.1899
2025-02-11 2024-12-31 13F COSTCO WHSL CORP COM 22160K105 3,679 59 1.63 3,371 5.05 0.1866
2024-11-12 2024-09-30 13F COSTCO WHSL CORP COM 22160K105 3,620 209 6.13 3,209 10.69 0.1923
2024-08-12 2024-06-30 13F COSTCO WHSL CORP COM 22160K105 3,411 280 8.94 2,900 26.43 0.1871
2024-05-09 2024-03-31 13F COSTCO WHSL CORP COM 22160K105 3,131 31 1.00 2,294 12.13 0.1608
2024-02-12 2023-12-31 13F COSTCO WHSL CORP COM 22160K105 3,100 119 3.99 2,046 21.44 0.1545
2023-11-14 2023-09-30 13F COSTCO WHSL CORP COM 22160K105 2,981 153 5.41 1,684 10.64 0.1376
2023-08-14 2023-06-30 13F COSTCO WHSL CORP COM 22160K105 2,828 1,365 93.30 1,523 109.64 0.1260
2023-05-12 2023-03-31 13F COSTCO WHSL CORP COM 22160K105 1,463 60 4.28 727 13.44 0.0662
2023-02-13 2022-12-31 13F COSTCO WHSL CORP COM 22160K105 1,403 10 0.72 641 -2.74 0.0683
2022-11-14 2022-09-30 13F COSTCO WHSL CORP COM 22160K105 1,393 -360 -20.54 658 -21.67 0.0828
2022-08-15 2022-06-30 13F COSTCO WHSL CORP COM 22160K105 1,753 -171 -8.89 840 -24.19 0.1310
2022-05-13 2022-03-31 13F COSTCO WHSL CORP COM 22160K105 1,924 -3 -0.16 1,108 1.28 0.1318
2022-02-10 2021-12-31 13F COSTCO WHSL CORP COM 22160K105 1,927 182 10.43 1,094 39.54 0.0974
2021-11-12 2021-09-30 13F COSTCO WHSL CORP COM 22160K105 1,745 0 0.00 784 13.62 0.0791
2021-08-16 2021-06-30 13F COSTCO WHSL CORP COM 22160K105 1,745 2 0.11 690 12.38 0.0708
2021-05-13 2021-03-31 13F COSTCO WHSL CORP COM 22160K105 1,743 -40 -2.24 614 -8.63 0.0737
2021-02-12 2020-12-31 13F COSTCO WHSL CORP COM 22160K105 1,783 525 41.73 672 50.34 0.0900
2020-11-12 2020-09-30 13F COSTCO WHSL CORP COM 22160K105 1,258 35 2.86 447 20.49 0.0684
2020-08-13 2020-06-30 13F COSTCO WHSL CORP COM 22160K105 1,223 1,223 371 0.0686
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.