diff --git a/CHANGELOG.md b/CHANGELOG.md
index 52a61fab2..5e22f8064 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,9 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 ## [Unreleased]
 
+### Removed
+- Removed unsupported `_common.mapping:SourceField`'s `mode` field and associated `_common.mapping:SourceFieldMode` enum ([#]())
+
 ## [0.1.0] - 2024-10-25
 
 ### Added
diff --git a/spec/schemas/_common.mapping.yaml b/spec/schemas/_common.mapping.yaml
index 2ec2dfbda..6523b2143 100644
--- a/spec/schemas/_common.mapping.yaml
+++ b/spec/schemas/_common.mapping.yaml
@@ -1202,14 +1202,6 @@ components:
           type: array
           items:
             type: string
-        mode:
-          $ref: '#/components/schemas/SourceFieldMode'
-    SourceFieldMode:
-      type: string
-      enum:
-        - disabled
-        - stored
-        - synthetic
     DataStreamTimestamp:
       type: object
       properties: