How does MPP affect open rates and engagement data?

MPP's impact on open rates and engagement data is substantial for lists with significant Apple Mail users. Open rates become artificially inflated as MPP pre fetches trigger tracking pixels without actual reading. Some senders report 20 to 40 percentage point increases in apparent opens from Apple device users.

This inflation makes open rates unreliable as engagement indicators. A 50% open rate might reflect 30% genuine opens plus 20% MPP pre fetches. Without knowing exactly which subscribers use MPP enabled devices, separating real engagement from artificial signals is impossible.

The practical response is treating opens as directionally useful rather than precise. Focus reporting on clicks, conversions, purchases, and replies, these metrics require genuine user action. Segment Apple device users if possible and apply different engagement assumptions. Many sophisticated senders have deprioritized opens entirely in favor of interaction based metrics.