diff --git a/fern/products/sdks/overview/ruby/changelog/2025-08-18.mdx b/fern/products/sdks/overview/ruby/changelog/2025-08-18.mdx
index 9460e8e23..e5751ca57 100644
--- a/fern/products/sdks/overview/ruby/changelog/2025-08-18.mdx
+++ b/fern/products/sdks/overview/ruby/changelog/2025-08-18.mdx
@@ -1,3 +1,6 @@
+## 1.0.0-rc9
+**`(fix):`** Union types extend the Model class.
+
 ## 1.0.0-rc8
 **`(fix):`** The client argument on the nested resource is now a keyword argument.