| 2015-10-09 | Sale | Costco Wholesale Corporation COST | Chairman of the Board | 84,986 0.0194% | $154.01 | $13.09M | +0.77% | |
| 2015-04-02 | Sale | Costco Wholesale Corporation COST | Chairman of the Board | 11,872 0.0027% | $151.65 | $1.8M | -1.86% | |
| 2015-04-01 | Sale | Costco Wholesale Corporation COST | Chairman of the Board | 187,128 0.0425% | $150.12 | $28.09M | -0.93% | |
| 2014-08-15 | Sale | Costco Wholesale Corporation COST | Chairman of the Board | 322,890 0.0493% | $79.46 | $25.66M | +21.86% | |
| 2013-11-15 | Sale | Costco Wholesale Corporation COST | Chairman of the Board | 117,892 0.0269% | $124.33 | $14.66M | -5.18% | |
| 2012-10-17 | Sale | Costco Wholesale Corporation COST | Former Chairman of the Board | 150,000 0.0134% | $37.35 | $5.6M | +19.56% | |
| 2012-06-21 | Sale | Costco Wholesale Corporation COST | Former Chairman of the Board | 47,756 0.0037% | $30.41 | $1.45M | +17.78% | |
| 2012-06-20 | Sale | Costco Wholesale Corporation COST | Former Chairman of the Board | 102,244 0.0078% | $30.41 | $3.11M | +16.24% | |
| 2011-11-17 | Sale | Costco Wholesale Corporation COST | Chairman of the Board | 39,898 – | $0 | $0 | +9.34% | |
| 2011-11-16 | Sale | Costco Wholesale Corporation COST | Chairman of the Board | 60,000 – | $0 | $0 | +8.02% | |
| 2011-04-26 | Sale | Costco Wholesale Corporation COST | Former Chairman of the Board | 50,000 0.0057% | $39.65 | $1.98M | +3.98% | |
| 2011-04-25 | Sale | Costco Wholesale Corporation COST | Former Chairman of the Board | 100,000 0.0115% | $39.65 | $3.96M | +5.37% | |
| 2010-12-21 | Sale | Costco Wholesale Corporation COST | Chairman of the Board | 82,993 – | $0 | $0 | +10.19% | |
| 2010-07-23 | Sale | Costco Wholesale Corporation COST | Former Chairman of the Board | 50,000 0.0113% | $55.38 | $2.77M | +29.77% | |
| 2010-07-14 | Sale | Costco Wholesale Corporation COST | Chairman of the Board | 100,000 – | $0 | $0 | +28.37% | |
| 2010-03-31 | Sale | Costco Wholesale Corporation COST | Chairman of the Board | 42,500 – | $0 | $0 | +6.56% | |
| 2010-03-30 | Sale | Costco Wholesale Corporation COST | Chairman of the Board | 57,500 – | $0 | $0 | +5.45% | |
| 2009-12-28 | Sale | Costco Wholesale Corporation COST | Former Chairman of the Board | 50,000 0.0099% | $52.50 | $2.63M | -1.24% | |
| 2009-11-18 | Sale | Costco Wholesale Corporation COST | Former Chairman of the Board | 100,000 0.0198% | $52.50 | $5.25M | -2.28% | |
| 2008-12-17 | Sale | Costco Wholesale Corporation COST | Chairman of the Board | 50,000 – | $0 | $0 | -9.5% |