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Lesson 5 of 7 · 4 min read

What Safari does to your clients’ data

Safari’s Intelligent Tracking Prevention (ITP) is the main reason Apple users vanish from marketing data. It is not one rule but several.

  1. Collect
  2. Store
  3. Use
  4. Activate

Third-party cookies are blocked

Cookies from another domain than the one in the address bar are blocked by default. Tracking that relies on them does not see Safari visitors come back.

Script cookies last 7 days

First-party cookies written by JavaScript, which is how most tags work, expire after 7 days. A visitor who returns on day 8 counts as new. After some ad clicks with tracking parameters, that can drop to 24 hours.

A separate tracking server is capped too

Cookies set by a server whose address is outside the website’s own network, such as a tracking subdomain pointed elsewhere, are capped at 7 days as well.

Click IDs get removed

In Private Browsing and in links opened from Mail and Messages, Safari strips known click IDs such as gclid and fbclid from the URL.

Key takeaways

  • Safari affects cookies, click IDs and returning-visitor recognition.
  • The 7-day cap applies to script cookies and to separate tracking servers.
  • Clients with a high Safari share and a long buying cycle lose the most.

For your marketing agency

Look at a client’s browser split in GA4. If Safari is a large share and their customers take more than a week to buy, part of their best audience is invisible today.