Costco Wholesale Corporation
MX ˙ BMV ˙ US22160K1051
SecurityMX:COST / Costco Wholesale Corporation
InstitutionRockland Trust Co
Latest Disclosed Ownership8,162 shares
Latest Disclosed Value $ 8,132,862
Rockland Trust Co reports 1.07% decrease in ownership of COST / Costco Wholesale Corporation

On April 16, 2026 - Rockland Trust Co filed a 13F-HR form disclosing ownership of 8,162 shares of Costco Wholesale Corporation (MX:COST) valued at $8,132,862 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 15, 2026 disclosing 8,250 shares of Costco Wholesale Corporation. This represents a change in shares of -1.07% 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)
2026-04-16 2026-03-31 13F COSTCO WHOLESALE COM 22160K105 8,162 -88 -1.07 8,133 14.31 0.3036
2026-01-15 2025-12-31 13F COSTCO WHSL CORP COM 22160K105 8,250 -108 -1.29 7,114 -8.04 0.2801
2025-11-06 2025-09-30 13F COSTCO WHSL CORP COM 22160K105 8,358 7,488 860.69 7,736 798.49 0.3170
2025-07-10 2025-06-30 13F COSTCO WHSL CORP COM 22160K105 870 4 0.46 861 5.13 0.0419
2025-04-16 2025-03-31 13F COSTCO WHSL CORP COM 22160K105 866 -231 -21.06 819 -18.51 0.0412
2025-01-14 2024-12-31 13F Costco Wholesale COM 22160K105 1,097 -93 -7.82 1,005 -4.65 0.0511
2024-10-03 2024-09-30 13F Costco Wholesale COM 22160K105 1,190 -886 -42.68 1,055 -40.25 0.0519
2024-07-23 2024-06-30 13F Costco Wholesale COM 22160K105 2,076 -35 -1.66 1,765 14.10 0.0930
2024-04-11 2024-03-31 13F Costco Wholesale COM 22160K105 2,111 -146 -6.47 1,547 3.83 0.0815
2024-01-11 2023-12-31 13F Costco Wholesale COM 22160K105 2,257 20 0.89 1,490 17.89 0.0815
2023-10-26 2023-09-30 13F Costco Wholesale COM 22160K105 2,237 -57 -2.48 1,264 2.27 0.0761
2023-07-27 2023-06-30 13F Costco Wholesale COM 22160K105 2,294 -45 -1.92 1,235 6.28 0.0738
2023-04-24 2023-03-31 13F Costco Wholesale COM 22160K105 2,339 -507 -17.81 1,162 116,100.00 0.0730
2023-01-24 2022-12-31 13F Costco Wholesale COM 22160K105 2,846 -73 -2.50 1 -99.93 0.0826
2022-10-19 2022-09-30 13F Costco Wholesale COM 22160K105 2,919 -224 -7.13 1,378 -8.50 0.0983
2022-07-13 2022-06-30 13F Costco Wholesale COM 22160K105 3,143 -101 -3.11 1,506 -19.42 0.1041
2022-04-18 2022-03-31 13F Costco Wholesale COM 22160K105 3,244 -406 -11.12 1,869 -9.84 0.1189
2022-01-27 2021-12-31 13F Costco Wholesale COM 22160K105 3,650 -477 -11.56 2,073 11.81 0.1320
2021-10-25 2021-09-30 13F Costco Wholesale COM 22160K105 4,127 171 4.32 1,854 18.47 0.1293
2021-07-21 2021-06-30 13F Costco Wholesale COM 22160K105 3,956 -165 -4.00 1,565 7.78 0.1082
2021-04-22 2021-03-31 13F Costco Wholesale COM 22160K105 4,121 249 6.43 1,452 -0.48 0.1046
2021-01-04 2020-12-31 13F Costco Wholesale COM 22160K105 3,872 174 4.71 1,459 11.12 0.1133
2020-10-08 2020-09-30 13F Costco Wholesale COM 22160K105 3,698 203 5.81 1,313 23.98 0.1128
2020-07-09 2020-06-30 13F Costco Wholesale COM 22160K105 3,495 163 4.89 1,059 11.36 0.0952
2020-04-16 2020-03-31 13F Costco Wholesale COM 22160K105 3,332 14 0.42 951 -2.46 0.0968
2020-01-06 2019-12-31 13F Costco Wholesale COM 22160K105 3,318 -83 -2.44 975 -0.81 0.0803
2019-10-11 2019-09-30 13F Costco Wholesale COM 22160K105 3,401 1,519 80.71 983 97.79 0.0894
2019-07-05 2019-06-30 13F COSTCO WHOLESALE CORP COMMON STOCK 22160K105 1,882 152 8.79 497 18.62 0.0493
2019-04-08 2019-03-31 13F COSTCO WHOLESALE CORP COMMON STOCK 22160K105 1,730 200 13.07 419 34.29 0.0444
2019-01-16 2018-12-31 13F COSTCO WHOLESALE CORP COMMON STOCK 22160K105 1,530 -140 -8.38 312 -20.41 0.0383
2018-10-05 2018-09-30 13F COSTCO WHOLESALE CORP COMMON STOCK 22160K105 1,670 -40 -2.34 392 9.80 0.0479
2018-07-06 2018-06-30 13F COSTCO WHOLESALE CORP COMMON STOCK 22160K105 1,710 5 0.29 357 11.21 0.0461
2018-04-10 2018-03-31 13F COSTCO WHOLESALE CORP COMMON STOCK 22160K105 1,705 385 29.17 321 30.49 0.0424
2018-01-11 2017-12-31 13F COSTCO WHOLESALE CORP COMMON STOCK 22160K105 1,320 1,320 246 0.0317
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.