Apple MPP
Mail Privacy Protection — Apple preloads images so classic open tracking no longer means a human opened the email.
Say it out loud
“Since 2021 Apple loads the tracking image automatically. Our open rate counts machines, not people.”
Apple Mail Privacy Protection proxies and prefetches images for Apple Mail users who opted in, which fires the open pixel without anyone reading anything. Because Apple Mail is a large share of consumer email, a substantial part of every open rate since September 2021 is machinery. Platforms that feed those opens into engagement scoring or revenue attribution will flatter you.
A number that should have made somebody suspicious.
Humans do not open at that rate within a minute. Machines do.
This was around 9% before September 2021. The denominator inflated; the numerator did not.
The clicks are real. The opens are a mixture.
Nobody's
Nothing to action — it changes a number or a risk you report.
What goes wrong
Building the engagement segment on opens. A sunset policy driven by opens will keep machine-opened dead addresses and cut genuinely interested people who read in a client that blocks images.
What people get told
The claim. “You can filter MPP opens out and get a clean number back.”
Actually. You can identify many of them and platforms do try. You cannot recover the pre-2021 metric, because a real Apple Mail user who genuinely read the email is indistinguishable from the prefetch. The correct response is to change which number you make decisions on, not to repair this one.
The dated rules behind this
A definition is not a citation. These are the pages with the primary source, the date it was published, and what to do about it.
- Open rate is not a measurement any moreGlobal · Apple
- Klaviyo counts Apple machine opens toward revenue by defaultGlobal · Klaviyo
See also
Where this sits
Stop 7, a human reacts. Somebody opens, clicks, ignores, unsubscribes, or presses the button that costs you the most.