Should email service providers filter clicks from iCloud Private Relay IPs?

Summary

Experts and marketers largely agree that email service providers should not implement blanket filtering of clicks from iCloud Private Relay IPs. Documentation clarifies that Private Relay obscures user IP addresses, presenting anonymized or generic IPs to ESPs. This is designed to protect user privacy, and RFC/IETF guidelines recommend working with, not against, such anonymization methods. While Private Relay impacts tracking accuracy (location, browsing activity) and may affect open metrics due to a mix of human and machine-generated traffic, blocking these IPs outright risks losing genuine engagement data and harming sender reputation. A nuanced approach is recommended, including analyzing click behavior for bot-like activity, tracking Private Relay engagement separately, A/B testing filtering strategies, and exploring alternative, non-IP-based tracking methods. Ethical considerations surrounding user privacy should also be paramount.

Key findings

  • IP Obfuscation & Anonymization: Private Relay obscures user IPs, providing anonymized/generic IPs to ESPs, primarily for privacy.
  • Legitimate Engagement: Clicks from Private Relay IPs are often legitimate, representing real user engagement.
  • Inaccurate Metrics: Filtering Private Relay IPs can lead to inaccurate engagement metrics and skew data.
  • Sender Reputation Risk: Aggressive filtering can negatively impact sender reputation.
  • Ethical Considerations: Filtering anonymized IPs can be perceived as a privacy violation.

Key considerations

  • Analyze Click Behavior: Identify and filter only bot-like activity originating from Private Relay IPs.
  • Separate Tracking: Track engagement from Private Relay IPs separately for a clearer picture.
  • A/B Testing: Experiment with different filtering approaches via A/B testing.
  • Alternative Methods: Explore non-IP-based tracking methods to respect user privacy.
  • Monitor Deliverability: Closely monitor deliverability metrics when implementing any filtering rules.
  • Support Anonymization: Follow IETF/RFC guidelines by supporting user-privacy-enhancing anonymization technologies.

What email marketers say
7Marketer opinions

The consensus among email marketers is that a blanket ban on filtering clicks from iCloud Private Relay IPs is not recommended. While Private Relay obscures IP addresses and impacts tracking accuracy, blocking these IPs entirely risks losing genuine engagement data and potentially harming sender reputation. A more nuanced approach is favored, involving analyzing click behavior for bot-like activity, tracking Private Relay engagement separately, and A/B testing different filtering strategies. Ethical concerns about user privacy should also be considered, with some suggesting alternative, non-IP-based tracking methods.

Key opinions

  • Blanket Ban Not Recommended: Filtering all iCloud Private Relay IPs is generally discouraged due to the risk of blocking legitimate user engagement.
  • Impact on Tracking Accuracy: Private Relay hides IP addresses, making it difficult to accurately track user location and browsing activity.
  • Potential Harm to Sender Reputation: Aggressively filtering Private Relay IPs could negatively impact sender reputation if legitimate users are blocked.
  • Privacy Concerns: Filtering anonymized IPs may be viewed as a violation of user privacy.

Key considerations

  • Analyze Click Behavior: Analyze click behavior from Private Relay IPs to identify and filter only those exhibiting bot-like characteristics.
  • Monitor Deliverability Metrics: Carefully monitor deliverability metrics before implementing any filtering rules.
  • Track Engagement Separately: Track engagement from Private Relay IPs separately and adjust marketing strategies accordingly.
  • A/B Testing: A/B test different filtering approaches to optimize engagement and deliverability.
  • Alternative Tracking Methods: Explore alternative tracking methods that don't rely on IP addresses.
Marketer view

Email marketer from Privacy Matters Blog argues that filtering anonymized IPs could be seen as a violation of user privacy. They suggest exploring alternative tracking methods that don't rely on IP addresses.

February 2024 - Privacy Matters Blog
Marketer view

Email marketer from Reddit suggests that filtering all iCloud Private Relay IPs might be too aggressive. They recommend analyzing click behavior from these IPs to identify and filter only those exhibiting bot-like characteristics, rather than a blanket ban.

October 2023 - Reddit
Marketer view

Email marketer from StackExchange notes that Apple Private Relay hides the IP address, making it difficult to track the user's location or browsing activity. This impacts open and click tracking, requiring marketers to adjust their strategies.

August 2022 - StackExchange
Marketer view

Email marketer from Email Marketing Tips Blog suggests implementing a hybrid approach: track engagement from Private Relay IPs separately, and adjust marketing strategies accordingly. This balances data accuracy and respects user privacy.

April 2022 - Email Marketing Tips Blog
Marketer view

Email marketer from Email Testing Blog recommends A/B testing different filtering approaches to see which yields the best results in terms of engagement and deliverability. They suggest comparing a control group with no filtering to groups with varying degrees of filtering.

May 2021 - Email Testing Blog
Marketer view

Email marketer from Deliverability Discussions Forum warns that aggressively filtering Private Relay IPs could negatively impact sender reputation if legitimate users are inadvertently blocked. They advise carefully monitoring deliverability metrics before implementing any filtering rules.

December 2023 - Deliverability Discussions Forum
Marketer view

Email marketer from Email Marketing Forum shares that blocking Apple Private Relay IPs completely would mean potentially losing genuine engagement data and recommends a more nuanced approach, such as monitoring click patterns instead of outright blocking.

April 2022 - Email Marketing Forum

What the experts say
3Expert opinions

Experts suggest that filtering or blocking clicks from iCloud Private Relay IPs is not recommended due to the likelihood of inaccurate metrics and the potential loss of legitimate user engagement data. Apple Private Relay uses a VPN-like system which uses the same IP addresses for multiple users. While traffic from these IPs is anonymized, actual clicks are mostly legitimate. Consideration should be given to the mix of human and machine-generated traffic from these IPs, especially when using the data for open metrics, with a focus on overall engagement trends rather than IP-based filtering.

Key opinions

  • Legitimate Clicks: Clicks from iCloud Private Relay IPs are mostly legitimate user actions.
  • Inaccurate Metrics: Filtering or blocking these IPs can lead to inaccurate engagement metrics.
  • VPN-like Behavior: Apple Private Relay uses the same set of IPs for multiple users.
  • Anonymized Traffic: Traffic from Private Relay IPs is anonymized, requiring a different approach to analysis.

Key considerations

  • Engagement Trends: Focus on overall engagement trends rather than relying solely on IP-based filtering.
  • Mix of Traffic: Consider the mix of human and machine-generated traffic from these IPs when analyzing open metrics.
  • Avoid Blanket Blocking: Avoid blanket blocking of Private Relay IPs to prevent losing legitimate user engagement data.
  • Re-evaluate Open Metrics: Re-evaluate how open metrics are used due to the VPN-like behaviour masking data.
Expert view

Expert from Word to the Wise suggests that filtering or blocking iCloud Private Relay IPs may cause inaccurate metrics. She recommends considering that clicks coming from these IPs could still represent legitimate user engagement, and that focusing on overall engagement trends might be a better strategy.

October 2022 - Word to the Wise
Expert view

Expert from Email Geeks explains that Apple Private Relay clicks come from the same set of IPs with the same UA because they're doing VPN-like things, and these are probably legit clicks, not just Apple checking links for safety.

October 2023 - Email Geeks
Expert view

Expert from Email Geeks shares that traffic from iCloud Private Relay IPs is anonymized and actual clicks will be mostly legitimate. Using data from these ranges for open metrics requires some thought as it will be a mix of human and machine generated for images.

May 2021 - Email Geeks

What the documentation says
5Technical articles

Documentation from Apple, RFC, IETF, Mozilla, and Cloudflare collectively explains that iCloud Private Relay obscures user IP addresses by routing traffic through multiple servers, resulting in ESPs seeing anonymized or generic IPs. This anonymization is intended to protect user privacy. Standards organizations like RFC and IETF recommend transparency and cooperation with anonymization methods, supporting these technologies while ensuring services remain functional. Because Private Relay operates similarly to a VPN, it's crucial to understand VPN technologies for a full picture of how IPs are hidden.

Key findings

  • IP Obfuscation: Private Relay hides user IP addresses by routing traffic through multiple servers.
  • Anonymized IPs: ESPs see anonymized or generic IP addresses associated with Apple's relay servers.
  • Privacy Protection: The primary purpose of Private Relay is to protect user privacy.
  • Transparency Recommended: Standards organizations recommend transparency and cooperation with anonymization methods.
  • VPN Similarity: Private Relay operates similarly to a VPN, masking IP addresses.

Key considerations

  • Adapt to Anonymization: Adapt email marketing and deliverability strategies to account for IP anonymization.
  • Support Privacy: Support user privacy by not attempting to circumvent Private Relay's IP obfuscation.
  • Functional Services: Ensure email services remain functional while respecting user privacy and anonymization technologies.
  • Consider VPN Impact: Understand how VPNs impact IP-based tracking and adjust analytics accordingly.
Technical article

Documentation from Apple Developer Documentation explains that Private Relay obscures user IP addresses, routing traffic through multiple servers. This means that ESPs will see anonymized or generic IP addresses associated with Apple's relay servers, rather than the user's actual IP address.

August 2023 - Apple Developer Documentation
Technical article

Documentation from Mozilla explains how VPNs work in general and how they hide IP addresses. This is relevant for iCloud private relay as it operates as a VPN.

October 2022 - Mozilla
Technical article

Documentation from Cloudflare specifies what technologies are available to anonymize data and IP addresses. This is relevant for iCloud private relay as it operates in similar ways.

November 2024 - Cloudflare
Technical article

Documentation from RFC specifies general guidelines for anonymizing client IP addresses, emphasizing the importance of protecting user privacy. It highlights techniques like IP masking and proxying, which are relevant to understanding how services like iCloud Private Relay operate.

December 2024 - RFC
Technical article

Documentation from IETF provides recommendations for providers to be transparent and work with anonymization methods. This includes supporting anonymization technologies and ensuring that services remain functional while respecting user privacy.

March 2021 - IETF