What is iCloud Private Relay?

iCloud Private Relay is a privacy service from Apple that encrypts a user's web browsing traffic and routes it through two separate internet relays. This process conceals the user's IP address from websites and network providers, preventing tracking. For more details, refer to what you need to know about iCloud Private Relay .

What are the risks of filtering iCloud Private Relay clicks?

Filtering legitimate clicks from iCloud Private Relay IPs can lead to underreported click-through rates, skew campaign performance data, and potentially harm sender reputation by suppressing positive engagement signals to mailbox providers. It also inaccurately flags genuine user activity as bot traffic.

How does Private Relay differ from Apple Mail Privacy Protection (MPP)?

iCloud Private Relay primarily affects click tracking by obscuring the user's IP address. Apple Mail Privacy Protection (MPP), on the other hand, mainly impacts open rate metrics by pre-fetching images. While both are privacy features, they address different aspects of email tracking.

What should ESPs do instead of filtering Private Relay clicks?

ESPs should focus on implementing more advanced bot detection mechanisms that analyze user behavior beyond just IP and user agent. This includes looking at conversion events, time on site, and other post-click engagement signals. Educating clients about these privacy changes and their impact on data is also important.

Are clicks from iCloud Private Relay IPs legitimate?

Yes, clicks from Apple's Private Relay IP addresses are generally considered legitimate user engagement. The service is designed to enhance user privacy, not to generate artificial clicks or mislead tracking systems. Filtering them would remove real user interactions from your metrics.

Should email service providers filter clicks from iCloud Private Relay IPs? - Sender reputation - Email deliverability - Knowledge base

The advent of privacy-focused features like iCloud Private Relay has introduced new complexities for email service providers. This service, designed to protect user privacy by obscuring IP addresses, presents a unique challenge when it comes to click tracking and bot detection. The fundamental question for many ESPs is whether clicks originating from these anonymized IP addresses should be filtered.

Many systems are configured to flag unusual click patterns, such as multiple clicks from a single IP or user agent, as potential bot activity. However, given how iCloud Private Relay functions, applying these traditional filtering rules can inadvertently impact the accuracy of client data and email deliverability.

How iCloud Private Relay affects email tracking

iCloud Private Relay works by routing a user's internet traffic through two separate internet relays. The first relay, operated by Apple, knows the user's IP address but not the website they are visiting. The second relay, operated by a third-party content provider, knows the website being visited but not the user's IP address. This dual-hop architecture ensures that no single entity can identify both the user and their browsing activity, providing a significant privacy enhancement. You can learn more about how to protect your web browsing from Apple.

For email, this means that when an Apple device user clicks a link in an email while Private Relay is active, the IP address recorded by the ESP's click tracking system will be that of the Private Relay exit node, not the user's actual IP. This pooling of traffic through a limited set of IP ranges can make these clicks appear to originate from a data center IP and potentially trigger bot detection rules that rely on IP diversity. It is important to distinguish this from Apple Mail Privacy Protection (MPP), which primarily impacts open rate tracking by pre-fetching images.

Understanding iCloud Private Relay

Apple's iCloud Private Relay aims to provide a more private browsing experience by concealing users' IP addresses. For ESPs, this means that clicks from Private Relay IPs are legitimate user actions, not necessarily malicious or bot-generated. Filtering these can lead to underreporting of true engagement.

Why filtering these IPs is problematic

Filtering all clicks from iCloud Private Relay IPs, simply because they exhibit similar characteristics (e.g., same IP, same user agent), is a problematic approach. The intention behind such filtering is usually to identify and exclude bot activity that inflates click metrics or drains campaign budgets through false engagement. However, in the case of Private Relay, these are real users engaging with your emails.

The core issue is that Private Relay aggregates a large number of legitimate users behind a smaller pool of IP addresses. If an ESP's system is too aggressive in flagging traffic from these shared IPs as suspicious, it will incorrectly filter out genuine user engagement. This can lead to inaccurate reporting of campaign performance and a misunderstanding of audience behavior. This is similar to how free email services click links to check for spam, but differs in intent and impact.

Traditional bot detection

Traditional bot detection often relies on identifying patterns that deviate from typical human behavior. This includes a high volume of clicks from a single IP address, rapid successive clicks, or clicks from known data center IP ranges not associated with end-users. The underlying assumption is that a unique user has a unique IP address or a distinct user agent string.

iCloud Private Relay traffic

iCloud Private Relay centralizes traffic through a limited number of exit nodes. This means many distinct users will appear to originate from the same IP, mimicking bot-like characteristics. User agent strings may also be standardized, further complicating traditional detection methods. This anonymity is designed for privacy, not to mislead ESPs.

Deliverability and metric implications

Filtering legitimate clicks, even if they come from anonymized IPs, can have adverse effects on deliverability. Mailbox providers assess sender reputation based on various factors, including user engagement. If an ESP consistently filters out a significant portion of actual clicks, it might inadvertently suppress positive engagement signals that contribute to a healthy sender reputation. This can contribute to iCloud emails being marked as spam.

Accurate click data is also crucial for marketers to understand campaign effectiveness, segment audiences, and optimize future sends. Masking or removing these clicks based on a flawed heuristic undermines the very purpose of email analytics. It's essential for ESPs to adapt their measurement strategies to accommodate privacy features, similar to how they've adjusted for proxy opens impacting inbox delivery.

Metric	Impact of filtering Private Relay clicks	Impact of not filtering
Click-through rate	Underreported, leading to a false perception of lower engagement.	Accurate reflection of user engagement, aiding campaign optimization.
Sender reputation	Potentially harmed due to suppressed positive signals to ISPs.	Maintained or improved, as ISPs see consistent, genuine engagement.
Bot detection accuracy	Skewed, as legitimate user clicks are misidentified as bot activity.	Improved, allowing focus on genuinely suspicious activity.

Recommended approach for ESPs

The recommended approach for ESPs is to avoid filtering clicks from iCloud Private Relay IPs as a default action. Instead, focus should be placed on more sophisticated bot detection methods that do not rely solely on IP address or user agent homogeneity. This involves analyzing a broader range of behavioral patterns.

ESPs should develop (or integrate) systems that can differentiate between legitimate, anonymized traffic and actual malicious bot activity. This might include analyzing click velocity, subsequent page views, conversion actions, or other post-click engagement signals. These deeper behavioral insights provide a more accurate picture of user intent than IP address alone.

Educating clients about these privacy features and their impact on data reporting is also crucial. Transparency helps manage expectations and ensures clients understand why certain metrics might appear differently. Maintaining strong email authentication protocols like DMARC, SPF, and DKIM remains foundational for deliverability, regardless of IP anonymization.

Views from the trenches

Best practices

Do not filter clicks from iCloud Private Relay IPs based on IP similarity or user agent alone; these are likely legitimate users.

Implement advanced bot detection that analyzes deeper behavioral patterns such as post-click activity, conversion rates, and time spent on page.

Educate clients about the effects of privacy features like Private Relay on click metrics and the importance of adapting reporting.

Common pitfalls

Over-filtering legitimate clicks from Private Relay IPs, which leads to underreporting of campaign performance and inaccurate client data.

Relying solely on IP address or user agent consistency as primary indicators for bot activity, especially with anonymizing services.

Misinterpreting the intent behind iCloud Private Relay, viewing it as a threat to data rather than a user privacy enhancement.

Expert tips

Regularly review your filtering rules and thresholds to ensure they are not inadvertently blocking legitimate engagement from privacy-conscious users.

Consider leveraging engagement metrics beyond simple clicks, such as website interactions or purchases, to measure true campaign success.

Collaborate with deliverability experts and other ESPs to share insights and best practices for navigating the evolving privacy landscape.

Marketer view

A marketer from Email Geeks says their system had been filtering iCloud Private Relay IPs based on a rule that flags multiple clicks from the same IP and User Agent as bot activity. They noted that the IPs do not appear suspicious and metrics show normal user behavior, suggesting the filtering might be unnecessary.

2023-05-10 - Email Geeks

Expert view

An expert from Email Geeks says that due to how Apple's Private Relay operates, it is expected to see many clicks originating from the same set of IP addresses and User Agents, as it functions like a VPN. They concluded that these clicks are likely legitimate and not merely Apple checking link safety.

2023-05-10 - Email Geeks

Navigating privacy and deliverability

The privacy landscape in email is continuously evolving, and features like iCloud Private Relay are a clear indication of this trend. For email service providers, the question of whether to filter clicks from these anonymized IPs boils down to a balance between maintaining data integrity and respecting user privacy. Overly aggressive filtering based on outdated heuristics not only misrepresents engagement but can also inadvertently affect deliverability.

Instead of filtering, the focus should be on developing more sophisticated analysis techniques that can accurately discern genuine user engagement from bot activity, regardless of IP anonymization. By adapting to these changes, ESPs can continue to provide valuable insights to their clients while upholding the privacy expectations of modern email users.