diff --git a/docs/release-notes/.FSharp.Compiler.Service/9.0.300.md b/docs/release-notes/.FSharp.Compiler.Service/9.0.300.md
index 1c78cff8fe9..491273fa561 100644
--- a/docs/release-notes/.FSharp.Compiler.Service/9.0.300.md
+++ b/docs/release-notes/.FSharp.Compiler.Service/9.0.300.md
@@ -12,6 +12,7 @@
 * Cancellable: fix leaking cancellation token ([PR #18295](https://github.com/dotnet/fsharp/pull/18295))
 * Fix NRE when accessing nullable fields of types within their equals/hash/compare methods ([PR #18296](https://github.com/dotnet/fsharp/pull/18296))
 * Fix nullness warning for overrides of generic code with nullable type instance ([Issue #17988](https://github.com/dotnet/fsharp/issues/17988), [PR #18337](https://github.com/dotnet/fsharp/pull/18337))
+* Unsafe downcast from `obj` to generic `T` no longer requires `not null` constraint on `T`([Issue #18275](https://github.com/dotnet/fsharp/issues/18275), [PR #18343](https://github.com/dotnet/fsharp/pull/18343))
 
 ### Added
 * Added missing type constraints in FCS. ([PR #18241](https://github.com/dotnet/fsharp/pull/18241))