Mickey has a post up about how long senders must hold on to that suppression list.
Jun
04
2008
One Response
Stay in touch with the conversation, subscribe to the RSS feed for comments on this post.
Subscribe
Word to the Wise
Email, Delivery, Spam and more
Categories:
Hey Laura…
Just wanted to point out that the ideas of “storing a suppression list for a long time” and “maintaining privacy of people that unsubscribe” don’t have to be at odds with each other.
If people would just hash their suppression lists before they share them with others (and they could hash them for internal storage too, if they are concerned with the security of their own networks) then there’s a really good chance (depending on the hash format chosen) that those addresses will never be discovered, but they can still be used for suppression.
MD5 or SHA-256 are the two hashing formats I’d recommend be used: MD5 because any reputable marketing company with half decent technology can support it, and SHA-256 because it’s more secure long-term.