If you don't left click on the field/number/ etc on Forms view - there isn't a tick mark.

So...don't click.

OR, do you mean how to clear all of them from a client's file?  Go to View on the upper menu bar, down 3/4 of the way down and there are some choices (clear audit checks *all*,  *current form* , show all audit checks). 

I do not see any way to do so, other than not to click on any results on the tax return. They are audit check marks. They do change color when the results change. I love them. They do not print anywhere.