tvOS 12.3 (build 16M153) is an official Apple over-the-air update for the Apple TV 4 (2015), released on 2019-05-13T17:20:32Z. The update package is 413.8 MB. This is a delta (partial) update that requires 12.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 9378ac176e4566cd881c8782d252490ec5784e69.zip.