diff --git a/fern/products/sdks/generators/typescript/changelog/2026-04-29.mdx b/fern/products/sdks/generators/typescript/changelog/2026-04-29.mdx
index 212bf2d9a1..3b1d380467 100644
--- a/fern/products/sdks/generators/typescript/changelog/2026-04-29.mdx
+++ b/fern/products/sdks/generators/typescript/changelog/2026-04-29.mdx
@@ -1,3 +1,9 @@
+## 3.66.6
+**`(fix):`** Fix TS2322 type error in generated serialization files when `enableForwardCompatibleEnums` is enabled.
+The enum schema builder now uses `forwardCompatibleEnum_` which correctly widens the parsed type to `string`,
+matching the widened API type.
+
+
 ## 3.66.5
 **`(fix):`** Fix generated wire tests for SSE endpoints with protocol-discriminated unions.
 The expected event assertion no longer wraps the deserialized data in a duplicate