Costco Wholesale Corporation
MX ˙ BMV ˙ US22160K1051
SecurityMX:COST / Costco Wholesale Corporation
InstitutionWelch Group, LLC
Latest Disclosed Ownership2,029 shares
Latest Disclosed Value $ 2,021,769
Welch Group, LLC reports 11.24% decrease in ownership of COST / Costco Wholesale Corporation

On April 21, 2026 - Welch Group, LLC filed a 13F-HR form disclosing ownership of 2,029 shares of Costco Wholesale Corporation (MX:COST) valued at $2,021,769 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 26, 2026 disclosing 2,286 shares of Costco Wholesale Corporation. This represents a change in shares of -11.24% 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)
2026-04-21 2026-03-31 13F COSTCO WHOLESALE COMMON 22160K105 2,029 -257 -11.24 2,022 2.54 0.0760
2026-01-26 2025-12-31 13F COSTCO WHSL CORP COMMON STOCK 22160K105 2,286 478 26.44 1,971 17.81 0.0760
2025-10-14 2025-09-30 13F COSTCO WHSL CORP COMMON 22160K105 1,808 53 3.02 1,674 -3.68 0.0653
2025-07-25 2025-06-30 13F COSTCO WHSL CORP COMMON 22160K105 1,755 -93 -5.03 1,737 1.11 0.0726
2025-04-08 2025-03-31 13F COSTCO WHSL CORP COMMON 22160K105 1,848 -57 -2.99 1,718 -2.16 0.0756
2025-01-27 2024-12-31 13F COSTCO WHSL CORP COMMON 22160K105 1,905 55 2.97 1,757 7.07 0.0791
2024-10-24 2024-09-30 13F COSTCO WHSL CORP COMMON 22160K105 1,850 114 6.57 1,640 11.19 0.0713
2024-07-17 2024-06-30 13F COSTCO WHSL CORP COMMON 22160K105 1,736 8 0.46 1,476 16.60 0.0709
2024-04-09 2024-03-31 13F COSTCO WHSL CORP COMMON 22160K105 1,728 2 0.12 1,266 11.06 0.0628
2024-01-23 2023-12-31 13F COSTCO WHSL CORP Common 22160K105 1,726 -23 -1.32 1,139 15.28 0.0614
2023-10-18 2023-09-30 13F COSTCO WHSL CORP Common 22160K105 1,749 -158 -8.29 988 -3.70 0.0585
2023-07-18 2023-06-30 13F COSTCO WHSL CORP Common 22160K105 1,907 64 3.47 1,027 12.13 0.0589
2023-04-13 2023-03-31 13F COSTCO WHSL CORP Common 22160K105 1,843 124 7.21 916 16.71 0.0532
2023-01-30 2022-12-31 13F COSTCO WHSL CORP Common 22160K105 1,719 647 60.35 785 54.94 0.0449
2022-10-13 2022-09-30 13F COSTCO WHSL CORP COMMON 22160K105 1,072 0 0.00 506 -1.56 0.0329
2022-07-21 2022-06-30 13F COSTCO WHSL CORP COMMON 22160K105 1,072 30 2.88 514 -14.33 0.0314
2022-04-29 2022-03-31 13F COSTCO WHSL CORP COMMON 22160K105 1,042 -2,673 -71.95 600 -71.55 0.0343
2022-01-26 2021-12-31 13F COSTCO WHSL CORP COMMON 22160K105 3,715 3,206 629.86 2,109 820.96 0.1234
2021-11-05 2021-09-30 13F COSTCO WHSL CORP COMMON 22160K105 509 509 229 0.0155
2019-01-10 2018-12-31 13F Costco Whsl Corp Common 22160K105 0 -528 -100.00 0 -100.00
2018-11-01 2018-09-30 13F Costco Whsl Corp Common 22160K105 528 0 0.00 124 12.73 0.0129
2018-07-30 2018-06-30 13F Costco Whsl Corp Common 22160K105 528 -60 -10.20 110 -0.90 0.0137
2018-04-23 2018-03-31 13F Costco Whsl Corp Common 22160K105 588 588 111 0.0141
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.