Costco Wholesale Corporation
MX ˙ BMV ˙ US22160K1051
SecurityMX:COST / Costco Wholesale Corporation
InstitutionD.B. Root & Company, LLC
Latest Disclosed Ownership2,852 shares
Latest Disclosed Value $ 2,841,382
D.B. Root & Company, LLC reports 0.59% decrease in ownership of COST / Costco Wholesale Corporation

On May 12, 2026 - D.B. Root & Company, LLC filed a 13F-HR form disclosing ownership of 2,852 shares of Costco Wholesale Corporation (MX:COST) valued at $2,841,382 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 3, 2026 disclosing 2,869 shares of Costco Wholesale Corporation. This represents a change in shares of -0.59% 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 COM 22160K105 2,852 -17 -0.59 2,841 14.83 0.6788
2026-02-03 2025-12-31 13F COSTCO WHSL CORP COM 22160K105 2,869 -271 -8.63 2,474 -14.87 0.6037
2025-11-06 2025-09-30 13F COSTCO WHSL CORP COM 22160K105 3,140 234 8.05 2,907 1.01 0.7377
2025-07-22 2025-06-30 13F COSTCO WHSL CORP COM 22160K105 2,906 -1 -0.03 2,877 4.66 0.8494
2025-05-14 2025-03-31 13F COSTCO WHSL CORP COM 22160K105 2,907 -92 -3.07 2,750 0.04 0.8878
2025-01-17 2024-12-31 13F COSTCO WHSL CORP COM 22160K105 2,999 -70 -2.28 2,748 1.03 0.8740
2024-10-31 2024-09-30 13F COSTCO WHSL CORP COM 22160K105 3,069 -508 -14.20 2,721 -10.53 0.8967
2024-07-15 2024-06-30 13F COSTCO WHSL CORP COM 22160K105 3,577 -149 -4.00 3,041 11.40 1.0374
2024-04-17 2024-03-31 13F COSTCO WHSL CORP COM 22160K105 3,726 166 4.66 2,730 16.13 0.9227
2024-01-16 2023-12-31 13F COSTCO WHSL CORP COM 22160K105 3,560 36 1.02 2,350 18.03 0.8520
2023-11-03 2023-09-30 13F COSTCO WHSL CORP COM 22160K105 3,524 141 4.17 1,991 9.34 0.7761
2023-07-18 2023-06-30 13F COSTCO WHSL CORP COM 22160K105 3,383 -34 -1.00 1,821 7.31 0.6890
2023-04-18 2023-03-31 13F COSTCO WHSL CORP COM 22160K105 3,417 55 1.64 1,698 10.63 0.6680
2023-01-27 2022-12-31 13F COSTCO WHSL CORP COM 22160K105 3,362 5 0.15 1,535 -3.22 0.6485
2022-10-26 2022-09-30 13F Costco Wholesale COM 22160K105 3,357 -72 -2.10 1,585 -3.53 0.7217
2022-07-21 2022-06-30 13F Costco Wholesale COM 22160K105 3,429 10 0.29 1,643 -16.51 0.7046
2022-05-06 2022-03-31 13F Costco Wholesale COM 22160K105 3,419 -476 -12.22 1,968 -10.99 0.7326
2022-02-01 2021-12-31 13F Costco Wholesale COM 22160K105 3,895 64 1.67 2,211 28.47 0.7973
2021-10-22 2021-09-30 13F Costco Wholesale COM 22160K105 3,831 43 1.14 1,721 14.89 0.6711
2021-07-28 2021-06-30 13F Costco Wholesale COM 22160K105 3,788 235 6.61 1,498 19.65 0.5594
2021-05-04 2021-03-31 13F Costco Wholesale COM 22160K105 3,553 601 20.36 1,252 12.59 0.4921
2021-02-09 2020-12-31 13F Costco Wholesale COM 22160K105 2,952 272 10.15 1,112 16.93 0.4440
2020-10-22 2020-09-30 13F Costco Wholesale COM 22160K105 2,680 -50 -1.83 951 14.99 0.3817
2020-08-06 2020-06-30 13F Costco Wholesale COM 22160K105 2,730 239 9.59 827 16.48 0.3591
2020-04-29 2020-03-31 13F Costco Wholesale COM 22160K105 2,491 56 2.30 710 -0.70 0.3583
2020-01-14 2019-12-31 13F Costco Wholesale COM 22160K105 2,435 -980 -28.70 715 -27.26 0.3149
2019-10-28 2019-09-30 13F Costco Wholesale COM 22160K105 3,415 430 14.41 983 24.75 0.4579
2019-07-19 2019-06-30 13F Costco Wholesale COM 22160K105 2,985 75 2.58 788 11.77 0.3492
2019-04-12 2019-03-31 13F Costco Wholesale Stock 22160K105 2,910 650 28.76 705 53.26 0.3009
2019-01-25 2018-12-31 13F/A-1 Costco Wholesale Stock 22160K105 2,260 162 7.72 460 -6.69 0.2288
2019-01-24 2018-12-31 13F Costco Wholesale Stock 22160K105 2,098 0 493 0.2172
2018-11-05 2018-09-30 13F Costco Wholesale Stock 22160K105 2,098 -618 -22.75 493 -13.20 0.2172
2018-07-25 2018-06-30 13F Costco Wholesale Stock 22160K105 2,716 -62 -2.23 568 8.60 0.2680
2018-05-02 2018-03-31 13F Costco Wholesale Stock 22160K105 2,778 527 23.41 523 24.82 0.2762
2018-02-22 2017-12-31 13F COSTCO WHSL CORP COM 22160K105 2,251 2,251 419 0.3589
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.