| 2011-06-14 | Sale | Costco Wholesale Corporation COST | director | 6,048 – | $0 | $0 | +6.08% | |
| 2010-12-21 | Sale | Costco Wholesale Corporation COST | director | 10,000 0.0023% | $72.42 | $724,200 | +10.19% | |
| 2010-12-13 | Sale | Costco Wholesale Corporation COST | director | 10,000 – | $0 | $0 | +12.21% | |
| 2010-10-29 | Sale | Costco Wholesale Corporation COST | director | 19,216 – | $0 | $0 | +22.24% | |
| 2010-10-20 | Sale | Costco Wholesale Corporation COST | director | 10,000 – | $0 | $0 | +22.2% | |
| 2010-10-11 | Sale | Costco Wholesale Corporation COST | director | 10,000 – | $0 | $0 | +17.19% | |
| 2010-03-15 | Sale | Costco Wholesale Corporation COST | director | 25,200 0.0032% | $33.75 | $850,500 | +1.86% | |
| 2007-10-12 | Sale | Costco Wholesale Corporation COST | director | 35,000 0.0044% | $36.91 | $1.29M | -1.25% | |
| 2007-08-27 | Sale | Costco Wholesale Corporation COST | director | 58,621 0.0132% | $61.72 | $3.62M | +9.55% | |
| 2007-08-24 | Sale | Costco Wholesale Corporation COST | director | 11,679 0.0026% | $61.70 | $720,594 | +8.33% | |
| 2007-08-23 | Sale | Costco Wholesale Corporation COST | director | 14,700 0.002% | $36.91 | $542,523 | +9.79% | |
| 2007-02-16 | Sale | Costco Wholesale Corporation COST | director | 84,000 0.0074% | $22.88 | $1.92M | +5.73% | |
| 2005-12-21 | Sale | Costco Wholesale Corporation COST | director | 10,000 0.0021% | $49.50 | $495,000 | +6.78% | |
| 2004-11-01 | Sale | Costco Wholesale Corporation COST | director | 24,000 0.0014% | $13.44 | $322,500 | -4.43% | |
| 2003-11-11 | Sale | Costco Wholesale Corporation COST | director | 20,000 0.0044% | $34.50 | $690,000 | +11.08% |