Costco Wholesale Corporation
MX ˙ BMV ˙ US22160K1051
SecurityMX:COST / Costco Wholesale Corporation
InstitutionThoroughbred Financial Services, Llc
Latest Disclosed Ownership8,759 shares
Latest Disclosed Value $ 8,728
Thoroughbred Financial Services, Llc reports 0.34% increase in ownership of COST / Costco Wholesale Corporation

On May 12, 2026 - Thoroughbred Financial Services, Llc filed a 13F-HR form disclosing ownership of 8,759 shares of Costco Wholesale Corporation (MX:COST) valued at $8,728 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 10, 2026 disclosing 8,729 shares of Costco Wholesale Corporation. This represents a change in shares of 0.34% 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)
2026-05-12 2026-03-31 13F COSTCO WHOLESALE CORPORATION COM Stock 22160K105 8,759 30 0.34 9 14.29 0.5211
2026-02-10 2025-12-31 13F COSTCO WHOLESALE CORPORATION COM Stock 22160K105 8,729 -547 -5.90 8 -12.50 0.4458
2025-11-10 2025-09-30 13F COSTCO WHSL CORP NEW COM Stock 22160K105 9,276 120 1.31 9 -11.11 0.5300
2025-08-08 2025-06-30 13F COSTCO WHSL CORP COM 22160K105 9,156 -4,230 -31.60 9 -25.00 0.6334
2025-05-09 2025-03-31 13F COSTCO WHSL CORP COM 22160K105 13,386 264 2.01 13 0.00 0.7903
2025-02-12 2024-12-31 13F COSTCO WHSL CORP COM 22160K105 13,122 269 2.09 12 9.09 0.7347
2024-11-08 2024-09-30 13F COSTCO WHSL CORP COM 22160K105 12,853 -332 -2.52 11 0.00 0.7349
2024-08-08 2024-06-30 13F COSTCO WHSL CORP COM 22160K105 13,185 2,050 18.41 11 37.50 0.7499
2024-05-07 2024-03-31 13F COSTCO WHSL CORP COM 22160K105 11,135 -1,382 -11.04 8 0.00 0.7847
2024-02-09 2023-12-31 13F COSTCO WHSL CORP COM 22160K105 12,517 1,595 14.60 8 33.33 0.6672
2023-11-08 2023-09-30 13F COSTCO WHSL CORP COM 22160K105 10,922 761 7.49 6 20.00 0.6051
2023-08-03 2023-06-30 13F COSTCO WHSL CORP COM 22160K105 10,161 302 3.06 5 25.00 0.7170
2023-04-24 2023-03-31 13F COSTCO WHSL CORP COM 22160K105 9,859 100 1.02 5 0.00 0.7236
2023-02-07 2022-12-31 13F COSTCO WHSL CORP COM 22160K105 9,759 210 2.20 4 -99.91 0.7280
2022-10-27 2022-09-30 13F COSTCO WHSL CORP COM 22160K105 9,549 55 0.58 4,510 -0.88 0.8591
2022-08-03 2022-06-30 13F COSTCO WHSL CORP COM 22160K105 9,494 690 7.84 4,550 -10.26 0.8381
2022-05-04 2022-03-31 13F COSTCO WHSL CORP COM 22160K105 8,804 3,717 73.07 5,070 75.61 0.8288
2022-02-09 2021-12-31 13F COSTCO WHSL CORP COM 22160K105 5,087 309 6.47 2,887 34.47 0.6052
2021-10-27 2021-09-30 13F COSTCO WHSL CORP COM 22160K105 4,778 257 5.68 2,147 20.01 0.5224
2021-07-27 2021-06-30 13F COSTCO WHSL CORP COM 22160K105 4,521 300 7.11 1,789 20.23 0.4480
2021-04-30 2021-03-31 13F COSTCO WHSL CORP COM 22160K105 4,221 1,374 48.26 1,488 38.81 0.4135
2021-01-26 2020-12-31 13F COSTCO WHSL CORP COM 22160K105 2,847 380 15.40 1,072 22.37 0.3323
2020-10-28 2020-09-30 13F COSTCO WHSL CORP COM 22160K105 2,467 105 4.45 876 22.35 0.3294
2020-07-20 2020-06-30 13F COSTCO WHSL CORP COM 22160K105 2,362 -3,537 -59.96 716 -57.43 0.2979
2020-04-23 2020-03-31 13F COSTCO WHSL CORP COM 22160K105 5,899 1,942 49.08 1,682 44.63 0.5992
2020-02-05 2019-12-31 13F COSTCO WHSL CORP COM 22160K105 3,957 199 5.30 1,163 7.39 0.3871
2019-11-12 2019-09-30 13F COSTCO WHSL CORP COM 22160K105 3,758 566 17.73 1,083 28.47 0.4107
2019-07-16 2019-06-30 13F/A-1 COSTCO WHSL CORP NEW Total COM 22160K105 3,192 503 18.71 844 29.49 0.3207
2019-07-16 2019-06-30 13F COSTCO WHSL CORP NEW Total COM 22160K105 843,708 841,019 843,708
2019-05-07 2019-03-31 13F COSTCO WHSL CORP COM 22160K105 2,689 232 9.44 651 30.20 0.2687
2019-02-13 2018-12-31 13F COSTCO WHSL CORP COM 22160K105 2,457 2,457 500 0.2453
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.