Main Street Research’s Costco COST Stock Holding History
Bought
Maintained
Sold
| Quarter | Market Value | Status | Shares |
Change in Stake | Trade Value | Portfolio Weight | Portfolio Position | |
|---|---|---|---|---|---|---|---|---|
|
2026
Q1 | $46M | Sell |
46,139
-16,227
| -26% | -$15.8M | 2.68% | 13 |
|
|
2025
Q4 | $53.8M | Sell |
62,366
-1,093
| -2% | -$990K | 3.08% | 15 |
|
|
2025
Q3 | $58.7M | Buy |
63,459
+610
| +1% | +$585K | 3.17% | 13 |
|
|
2025
Q2 | $62.2M | Buy |
62,849
+894
| +1% | +$889K | 3.87% | 5 |
|
|
2025
Q1 | $58.6M | Buy |
61,955
+663
| +1% | +$646K | 3.83% | 8 |
|
|
2024
Q4 | $56.2M | Buy |
61,292
+2,472
| +4% | +$2.29M | 3.5% | 9 |
|
|
2024
Q3 | $52.1M | Buy |
58,820
+1,458
| +3% | +$1.27M | 3.28% | 9 |
|
|
2024
Q2 | $48.8M | Buy |
57,362
+1,852
| +3% | +$1.45M | 3.22% | 9 |
|
|
2024
Q1 | $40.7M | Buy |
55,510
+4,804
| +9% | +$3.43M | 2.76% | 12 |
|
|
2023
Q4 | $34.2M | Buy |
50,706
+42,835
| +544% | +$25.4M | 2.75% | 11 |
|
|
2023
Q3 | $4.45M | Buy |
7,871
+37
| +0.5% | +$20.4K | 0.46% | 41 |
|
|
2023
Q2 | $4.22M | Sell |
7,834
-65
| -0.8% | -$32.9K | 0.67% | 29 |
|
|
2023
Q1 | $3.92M | Buy |
7,899
+250
| +3% | +$123K | 0.77% | 24 |
|
|
2022
Q4 | $3.49M | Buy |
7,649
+201
| +3% | +$98.2K | 0.85% | 19 |
|
|
2022
Q3 | $3.52M | Buy |
7,448
+238
| +3% | +$124K | 0.77% | 16 |
|
|
2022
Q2 | $3.46M | Sell |
7,210
-75,444
| -91% | -$38.3M | 0.91% | 15 |
|
|
2022
Q1 | $47.6M | Buy |
82,654
+11,805
| +17% | +$6.2M | 4.47% | 3 |
|
|
2021
Q4 | $40.2M | Buy |
70,849
+3,326
| +5% | +$1.7M | 3.11% | 9 |
|
|
2021
Q3 | $30.3M | Buy |
67,523
+1,550
| +2% | +$681K | 2.66% | 14 |
|
|
2021
Q2 | $26.1M | Buy |
65,973
+4,244
| +7% | +$1.6M | 2.1% | 21 |
|
|
2021
Q1 | $21.8M | Sell |
61,729
-3,090
| -5% | -$1.08M | 2.05% | 23 |
|
|
2020
Q4 | $24.4M | Buy |
64,819
+2,691
| +4% | +$1.01M | 2.63% | 8 |
|
|
2020
Q3 | $22.1M | Buy |
62,128
+1,972
| +3% | +$663K | 2.81% | 7 |
|
|
2020
Q2 | $18.2M | Buy |
60,156
+3,319
| +6% | +$1.01M | 2.86% | 7 |
|
|
2020
Q1 | $16.2M | Buy |
56,837
+50
| +0.1% | +$15.2K | 3.97% | 6 |
|
|
2019
Q4 | $16.7M | Buy |
56,787
+606
| +1% | +$180K | 2.63% | 11 |
|
|
2019
Q3 | $16.2M | Buy |
56,181
+46,089
| +457% | +$13M | 3.04% | 7 |
|
|
2019
Q2 | $2.67M | Buy |
10,092
+52
| +0.5% | +$13K | 0.6% | 30 |
|
|
2019
Q1 | $2.43M | Buy |
10,040
+879
| +10% | +$192K | 0.77% | 22 |
|
|
2018
Q4 | $1.87M | Sell |
9,161
-65,321
| -88% | -$14.6M | 0.73% | 22 |
|
|
2018
Q3 | $17.5M | Buy |
74,482
+4,634
| +7% | +$1.04M | 2.51% | 13 |
|
|
2018
Q2 | $14.6M | Sell |
69,848
-345
| -0.5% | -$68.2K | 2.29% | 19 |
|
|
2018
Q1 | $13.2M | Buy |
70,193
+3,400
| +5% | +$641K | 2.09% | 23 |
|
|
2017
Q4 | $12.4M | Sell |
66,793
-2,377
| -3% | -$410K | 1.89% | 27 |
|
|
2017
Q3 | $11.4M | Sell |
69,170
-353
| -0.5% | -$55.5K | 1.83% | 26 |
|
|
2017
Q2 | $11.1M | Buy |
69,523
+4,819
| +7% | +$830K | 1.82% | 25 |
|
|
2017
Q1 | $10.8M | Buy |
64,704
+3,023
| +5% | +$507K | 1.9% | 19 |
|
|
2016
Q4 | $9.88M | Buy |
61,681
+2,414
| +4% | +$369K | 1.92% | 20 |
|
|
2016
Q3 | $9.04M | Buy |
59,267
+221
| +0.4% | +$35.7K | 1.77% | 21 |
|
|
2016
Q2 | $9.27M | Buy |
59,046
+2,529
| +4% | +$383K | 1.92% | 21 |
|
|
2016
Q1 | $8.91M | Buy |
56,517
+134
| +0.2% | +$20.3K | 2.3% | 16 |
|
|
2015
Q4 | $9.11M | Buy |
56,383
+649
| +1% | +$103K | 1.95% | 18 |
|
|
2015
Q3 | $8.81M | Buy |
55,734
+3,554
| +7% | +$507K | 2.07% | 17 |
|
|
2015
Q2 | $7.05M | Buy |
52,180
+4,206
| +9% | +$605K | 1.44% | 32 |
|
|
2015
Q1 | $7.27M | Buy |
47,974
+1,017
| +2% | +$149K | 1.56% | 25 |
|
|
2014
Q4 | $6.66M | Buy |
46,957
+5,418
| +13% | +$736K | 1.43% | 29 |
|
|
2014
Q3 | $5.21M | Buy |
41,539
+1,930
| +5% | +$233K | 1.16% | 34 |
|
|
2014
Q2 | $4.56M | Buy |
39,609
+1,517
| +4% | +$174K | 1.08% | 37 |
|
|
2014
Q1 | $4.25M | Buy |
38,092
+6,764
| +22% | +$774K | 1.03% | 41 |
|
|
2013
Q4 | $3.73M | Buy |
31,328
+358
| +1% | +$42.8K | 0.93% | 44 |
|
|
2013
Q3 | $3.57M | Sell |
30,970
-2,210
| -7% | -$255K | 0.96% | 42 |
|
|
2013
Q2 | $3.67M | Buy |
+33,180
| New | +$3.63M | 1.11% | 35 |
|
Other funds holding COST
VCM
VPM
DAM
Main Street Research's COST Position: Q1 2026 in Review
Main Street Research reduced its Costco (COST) stake by 26% in Q1 2026, selling an estimated $15.8M and leaving 46,139 shares worth $46M. The position accounts for 2.68% of the portfolio, ranked #13.
Main Street Research first reported a position in COST in Q2 2013 and has held it in 52 quarters since. The position peaked at $62.2M in Q2 2025. 4,238 funds tracked by Wall St. Rank hold COST as of Q1 2026.
- Main Street Research held 46,139 shares of Costco worth $46M as of Q1 2026.
- Main Street Research sold 16,227 Costco shares in Q1 2026, an estimated $15.8M.
- Costco made up 2.68% of Main Street Research's portfolio in Q1 2026, its #13 holding.
- Main Street Research first reported a position in Costco in Q2 2013 and has held it in 52 quarters since.
- Main Street Research's Costco position peaked at $62.2M in Q2 2025.
- 4,238 funds tracked by Wall St. Rank held Costco as of Q1 2026.
Based on Main Street Research's 13F filing for Q1 2026, filed 30 Apr 2026.