You get email notifications when a company posts a new update you are a shareholder in or a community you are a member of.
You can unsubscribe from these emails by clicking the "Unsubscribe" at the bottom of those emails or by navigating here.
It will take you to this selection where you need to:
Choose what company/community you want to edit your preferences of
Unselect the email categories you don't want emails anymore
Click "Save."
You can always subscribe to these emails if you want.