We have a large pool of addresses that have said they do not want to be contacted. I'd like to use the API to add those to a suppression list so that clients do not inadvertently email someone who has opted out. I've seen from other messages on the board that there is not currently a way to add emails directly to the suppression list.
Using the API, is there a way to create or reuse an existing list, make sure that when people unsubscribe they are added to the suppression list, and then add and unsubscribe everyone?
As you say the functionality to suppress people via the api is not available, I've added your vote however so we may add this in a future update.
The default settings for a list is to suppress any email address which are unsubscribed, so your idea should work as expected in this case. If you have any troubles let us know.