| Oct 22, 2018 AForm 4 → | Oct 24, 5:51 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 1,179 | — | — | 9,833 | — | plan? |
| Oct 1, 2018 SForm 4 → | Oct 2, 5:08 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 3,000 | $235.81 | $707,430 | 12,000 | −20.0% | plan? |
| Sep 4, 2018 SForm 4 → | Sep 6, 10:33 am EDT | COSTCO WHOLESALE CORP /NEWCOST | 3,000 | $233.14 | $699,420 | 15,000 | −16.7% | plan? |
| Aug 1, 2018 SForm 4 → | Aug 3, 11:58 am EDT | COSTCO WHOLESALE CORP /NEWCOST | 3,000 | $218.65 | $655,950 | 18,000 | −14.3% | plan? |
| Jul 2, 2018 SForm 4 → | Jul 3, 12:52 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 3,000 | $208.42 | $625,260 | 21,000 | −12.5% | plan? |
| Jun 1, 2018 SForm 4 → | Jun 4, 1:27 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 3,000 | $195.45 | $586,350 | 24,000 | −11.1% | plan? |
| May 1, 2018 SForm 4 → | May 2, 2:29 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 3,000 | $196.49 | $589,470 | 27,000 | −10.0% | plan? |
| Apr 2, 2018 SForm 4 → | Apr 3, 2:07 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 3,000 | $186.91 | $560,730 | 30,000 | −9.09% | plan? |
| Mar 1, 2018 SForm 4 → | Mar 2, 11:25 am EST | COSTCO WHOLESALE CORP /NEWCOST | 3,000 | $191.31 | $573,930 | 33,000 | −8.33% | plan? |
| Feb 1, 2018 SForm 4 → | Feb 2, 10:10 am EST | COSTCO WHOLESALE CORP /NEWCOST | 3,000 | $193.41 | $580,230 | 36,000 | −7.69% | plan? |
| Jan 2, 2018 SForm 4 → | Jan 3, 3:13 pm EST | COSTCO WHOLESALE CORP /NEWCOST | 3,000 | $187.23 | $561,690 | 39,000 | −7.14% | plan? |
| Dec 1, 2017 SForm 4 → | Dec 4, 12:45 pm EST | COSTCO WHOLESALE CORP /NEWCOST | 3,000 | $183.26 | $549,780 | 42,000 | −6.67% | plan? |
| Nov 1, 2017 SForm 4 → | Nov 2, 11:03 am EDT | COSTCO WHOLESALE CORP /NEWCOST | 1,000 | $161.97 | $161,970 | 45,000 | −2.17% | plan? |
| Oct 22, 2017 AForm 4/A → | Oct 27, 4:54 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 1,680 | — | — | 8,654 | — | plan? |
| Oct 22, 2017 AForm 4 → | Oct 24, 6:18 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 1,870 | — | — | 8,844 | — | plan? amended |
| Oct 2, 2017 SForm 4 → | Oct 2, 6:10 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 1,000 | $164.92 | $164,920 | 46,000 | −2.13% | plan? |
| Sep 1, 2017 SForm 4 → | Sep 5, 8:58 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 1,000 | $157.59 | $157,590 | 47,000 | −2.08% | plan? |
| Aug 1, 2017 SForm 4/A → | Sep 7, 2:42 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 1,000 | $159.25 | $159,250 | 48,000 | −2.04% | plan? |
| Aug 1, 2017 SForm 4 → | Aug 2, 10:27 am EDT | COSTCO WHOLESALE CORP /NEWCOST | 1,000 | $159.25 | $159,250 | 4,974 | −16.7% | plan? amended |
| Jul 3, 2017 SForm 4/A → | Sep 7, 2:42 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 1,000 | $160.28 | $160,280 | 49,000 | −2.00% | plan? |
| Jul 3, 2017 SForm 4 → | Jul 5, 9:07 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 1,000 | $160.28 | $160,280 | 5,974 | −14.3% | plan? amended |
| May 24, 2017 AForm 4 → | May 25, 9:44 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 140 | $173.01 | $24,221 | 6,974 | — | plan? |
| Oct 22, 2016 AForm 4 → | Oct 24, 2:47 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 2,182 | — | — | 6,834 | — | plan? |
| Aug 17, 2016 SForm 4 → | Aug 18, 2:38 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 5,737 | $167.74 | $962,347 | 4,652 | −55.2% | plan? |
| Apr 27, 2016 MForm 4 → | Apr 28, 2:27 pm EDT | EXPEDITORS INTERNATIONAL OF WASHINGTON INCEXPD | 32,000 | $44.65 | $1,428,800 | 140,328 | — | plan? |
| Oct 22, 2015 AForm 4 → | Oct 26, 6:54 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 2,150 | — | — | 10,389 | — | plan? |
| May 20, 2015 AForm 4 → | May 22, 3:45 pm EDT | EXPEDITORS INTERNATIONAL OF WASHINGTON INCEXPD | 4,231 | — | — | 108,328 | — | plan? |
| Feb 27, 2015 AForm 4 → | Mar 3, 6:24 pm EST | COSTCO WHOLESALE CORP /NEWCOST | 216 | $146.96 | $31,743 | 8,947 | — | plan? |
| Oct 20, 2014 GForm 5 → | Oct 13, 2015, 12:12 pm EDT | COSTCO WHOLESALE CORP /NEWCOST | 708 | — | — | 8,239 | — | plan? |