DNE List: Approaches
•Give spammers the list
–Very bad idea: “whom-to-spam” list
–Can seed each spammer’s list with “telltale” addresses?  (Interesting CS theory problem.)
•Spammer submits their mailing list to DNE service; service returns “scrubbed” list
–Spammer still learns about some valid addresses
–Might be able to limit this by limiting access, charging for access, etc.
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