# ULA x Blue Origin (BE-4 Engine) revision history

Append-only Arc G field-change log. Forward-only honesty: events accrue from Arc G adoption.

Partnership: [ULA x Blue Origin (BE-4 Engine)](/partnerships/ula-x-blue-origin-be-4-engine.md)

## Recorded posture

- First recorded event: 2014-09-17
- Last material change: 2014-09-17
- Material event count: 1
- Editorial event count: 0

## Forward-only note

Arc G is forward-only. The event log accrues from the Arc G adoption point. Fields with no events post-baseline equal the current cached value and are not independently verified at any prior date.

_Canonical URL: /partnerships/ula-x-blue-origin-be-4-engine/history. REST: /v1/partnerships/f8a766c4-5c32-4734-a9a2-8cb5f8184130/history. HTML: [/partnerships/ula-x-blue-origin-be-4-engine/history](/partnerships/ula-x-blue-origin-be-4-engine/history)._