To see all alerts that have been triggered in the past 90 days, go to the Alerts History tab of the Alerts window. The alerts will automatically be listed sorted by date, with the most recent alerts at the top, but you can click any of the column headers to sort by that column. Mouseover a row to see a tooltip with more information about the alert.
If a single ticker alert was fired, the ‘Portfolio/Watchlist’ item for that ticker will be empty, but if the ticker triggered the alert for portfolio or watchlist, it will list which portfolio or watchlist.
You can delete an alert from your history by clicking the ‘x’ in the ‘Delete’ column.
To export the alert history to a .csv file click the ‘Export’ button in the top right hand corner highlighted in the screenshot below.