Since the release of iOS 17 / macOS Sonoma, Apple has significantly strengthened user privacy protections. One of the updates that has drawn the most attention from the marketing, advertising, and analytics industries is Link Tracking Protection (LTP).
LTP directly affects: Advertising click attribution (Google Ads, Meta Ads, etc.)、Marketing campaign tracking (Email, SMS, EDM)、E-commerce affiliate/redirection flows、Cross-site user identification
What Is Link Tracking Protection (LTP)?
LTP automatically removes tracking parameters from URLs to prevent users from being identified across different websites.
Apple defines “tracking parameters” as those that:
- Allow cross-site or cross-platform tracking of the same user (e.g., advertising click-IDs)
- Create a uniquely identifiable, fingerprint-level user identifier
Examples include:
?fbclid=xxx (Facebook / Meta) ?gclid=xxx (Google Ads) ?msclkid=xxx (Microsoft Ads) ?_gl=xxx (Google auto-tagging) ?mc_eid=xxx (MailChimp)
These parameters are automatically removed in certain contexts.
When Does LTP Automatically Remove These Parameters?
The table below summarizes LTP behavior across different scenarios:
| Scenario | Automatically Remove Tracking Parameters? |
|---|---|
| Safari Private Browsing | ✔ Yes |
| Clicking links in Messages (iMessage) | ✔ Yes |
| Clicking links in Mail (Mail app) | ✔ Yes |
| Safari “Link Preview” | ✔ Yes |
| Safari Regular Browsing | ❌ No (most commonly misunderstood) |
Important: In regular Safari browsing, most tracking parameters—including UTM—are NOT removed.
Which Parameters Does LTP Remove?
Confirmed removable tracking parameters (depending on scenario) include:
| Platform | Parameter |
|---|---|
| fbclid | |
| Google Ads | gclid |
| Google Analytics auto-tagging | _gl |
| Microsoft Ads | msclkid |
| MailChimp | mc_eid |
| HubSpot | hsenc |
| Criteo | ctag |
| Adobe | Certain custom unique IDs |
Note: LTP is not a simple fixed blacklist. Apple evaluates whether a parameter has personally identifiable or cross-site tracking capability, and any such parameter may be removed.
Are UTM Parameters Removed?
No.
utm_source, utm_medium, utm_campaign, utm_content, utm_term all remain intact.
Reason:
- UTM parameters identify traffic sources, not individual users
- They do not enable cross-site tracking
This is crucial for tools like GA4, Adobe Analytics, Mixpanel, and Amplitude.
Impact of LTP on Marketing, Analytics, and Advertising
If unique click-IDs (e.g., gclid, fbclid, other click_id values) are removed in certain scenarios, it directly impacts attribution accuracy.
iOS 17 Release Timeline
- June 2023 — First developer beta
- July 2023 — First public beta
- September 2023 — Full iOS 17 release
