Intersect with... except?

I want to send invitations to a list of emails EXCEPT the ones who have already been invited.
Does anyone have any idea how to do as there is no :filter on a list of text

I setup an exemple here :

Just a potential alternative if the list thing isn’t working out. While not the most efficient, perform a check right before you send the invite. In other words, keep the invite as a separate workflow that has the additional condition of checking if the user has been invited. This might not work if you batch process the list through some external API.

@Scott. Thank you.
True I could check before if the list contains an already send email (with intersect with for instance). But I wish the process is transparent for the user so he doesn’t have to remove all the already sent emails.

if you don’t use BCC, all users will see the e-mail of others and this isn’t good for spam avoidance (there were spam bots collecting e-mails from infected computers) and privacy (unless users consent to that)

Sure, I use bcc anyway for this. Problem is that I don’t want my users to many invitations = spammy.
Unfortunately, the only way I see to remove a list of text from another list of text is going through the ddb.