diff --git a/sdk/cosmosdb/cosmos/CHANGELOG.md b/sdk/cosmosdb/cosmos/CHANGELOG.md
index beaffc4e601d..bc0a98dc46d2 100644
--- a/sdk/cosmosdb/cosmos/CHANGELOG.md
+++ b/sdk/cosmosdb/cosmos/CHANGELOG.md
@@ -1,14 +1,10 @@
 # Release History
 
-## 3.12.2 (Unreleased)
+## 3.12.2 (2021-07-21)
 
 ### Features Added
 
-### Breaking Changes
-
-### Bugs Fixed
-
-### Other Changes
+- Adopted target ES2017 to reduce bundle size.
 
 ## 3.12.1 (2021-07-16)
 
diff --git a/sdk/cosmosdb/cosmos/tsconfig.json b/sdk/cosmosdb/cosmos/tsconfig.json
index d57433339043..8bb52a2ee886 100644
--- a/sdk/cosmosdb/cosmos/tsconfig.json
+++ b/sdk/cosmosdb/cosmos/tsconfig.json
@@ -9,7 +9,7 @@
     "outDir": "dist-esm",
     "preserveConstEnums": true,
     "removeComments": false,
-    "target": "es6",
+    "target": "ES2017",
     "newLine": "LF",
     "resolveJsonModule": true,
     "composite": true,