How does MPP work? (Image proxying, IP obfuscation)

MPP operates through two mechanisms: image proxying and IP obfuscation. When an email arrives, Apple's servers fetch all remote images and cache them, regardless of user action. This happens shortly after delivery, not when the recipient opens the message.

Because tracking pixels are just images (typically 1x1 transparent GIFs), they're fetched along with everything else. Your email platform registers an "open" even if the email sits unread or gets deleted without being viewed. The prefetch makes open timestamps meaningless and inflates open rates.

IP obfuscation means all image requests come from Apple's proxy servers, not the recipient's device. You see Apple's IP addresses, not the subscriber's. This breaks location tracking and device detection that relied on IP analysis.

The combination renders traditional open tracking ineffective for MPP users. You know the email was delivered, but you can't trust open signals to reflect actual human engagement.