COST
Costco Wholesale Corp
8 super-investors hold COST worth a combined $594M. The largest position: Christopher Bloomstran at 0.4% of their portfolio. This quarter the cohort logged 0 buys and 1 sell on the name. Cohort Conviction Score: 31 — ranked #323 of 724 scored stocks. Conviction easing: 1 fewer super-investor hold it than in 2025Q4.
Why super-investors own COST
Ownership of COST within this cohort is narrow and largely static: eight investors hold it, but the highest portfolio concentration is just 0.4%, shared by Christopher Bloomstran and Joel Greenblatt — the latter accounting for the bulk of the $594M combined value given his $543M position. The only move this quarter was Francois Rochon exiting entirely, nudging the cohort count back to its 2024 baseline of two after a brief expansion to three. No one added or initiated. The eight-quarter owner count — 2, 3, 3, 3, 3, 3, 3, 2 — suggests a cohort that treats COST as a peripheral, low-conviction holding rather than a core thesis, with interest neither building nor collapsing.
AI-synthesized from 13F filings. Not investment advice.
Cohort owners over time
2016Q2 → 2026Q1How many of the cohort members held this stock each quarter.
Owners (8) · click any column to sort
| #↑ | Manager | % Port. | History | Value | Shares |
|---|---|---|---|---|---|
| 1 | Joel Greenblatt | 0.4% | 39q | $543M | 544,795 |
| 2 | Thomas Gayner | 0.3% | 40q | $39M | 39,150 |
| 3 | Thomas Russo | 0.1% | 40q | $5M | 4,624 |
| 4 | Christopher Bloomstran | 0.4% | 40q | $3M | 3,367 |
| 5 | Mairs & Power Funds | <0.1% | 40q | $3M | 2,963 |
| 6 | Torray Funds | 0.1% | 15q | $626K | 628 |
| 7 | David Katz | 0.1% | 13q | $557K | 559 |
| 8 | Bill Nygren | 0.0% | 4q | $361K | 362 |
- 1Joel Greenblattport0.4%val$543M544,795 sh·39q held
- 2Thomas Gaynerport0.3%val$39M39,150 sh·40q held
- 3Thomas Russoport0.1%val$5M4,624 sh·40q held
- 4Christopher Bloomstranport0.4%val$3M3,367 sh·40q held
- 5Mairs & Power Fundsport<0.1%val$3M2,963 sh·40q held
- 6Torray Fundsport0.1%val$626K628 sh·15q held
- 7David Katzport0.1%val$557K559 sh·13q held
- 8Bill Nygrenport0.0%val$361K362 sh·4q held
Owners of COST also hold
Recent activity (1)
| Manager | Move | % Port. | Δ Shares | Value | Filed |
|---|---|---|---|---|---|
| Francois Rochon | EXIT | <0.1% | -100% | $0 | May 15, 2026 |
Long US equity 13F-HR filings only. CUSIP 22160K105. Not investment advice.