1. Third-party cookie blocking by default — 2003 (Safari 1.0); industry first.
2. Intelligent Tracking Prevention (ITP), using on-device machine learning to identify and limit cross-site trackers — 2017; industry first.
3. Storage Access API prompts for embedded third-party content (e.g., social login widgets) — 2018 (ITP 2.0); industry first (co-developed by WebKit, later adopted as a web standard).
4. Full third-party cookie blocking (no exceptions) — 2020 (ITP in Safari 13.1); industry first for a major browser.