Return Path: Phishing Attack: An Open Letter to the Anti-Spam and Mailbox Operator Community

“As you might expect, investigating a data breach of this kind takes a tremendous amount of post-hoc forensic work, so it’s taken us a little while to get our arms around exactly what happened. …Here’s what those two compromises looked like, what we’ve done about them, what we’re doing to monitor more aggressively for future compromises, and what we’d like to ask of you.”