diff --git a/compiler/src/dotty/tools/dotc/core/Definitions.scala b/compiler/src/dotty/tools/dotc/core/Definitions.scala
index eaafcca3992e..ea6652705e60 100644
--- a/compiler/src/dotty/tools/dotc/core/Definitions.scala
+++ b/compiler/src/dotty/tools/dotc/core/Definitions.scala
@@ -921,7 +921,6 @@ class Definitions {
   @tu lazy val ParamMetaAnnot: ClassSymbol = requiredClass("scala.annotation.meta.param")
   @tu lazy val SetterMetaAnnot: ClassSymbol = requiredClass("scala.annotation.meta.setter")
   @tu lazy val ShowAsInfixAnnot: ClassSymbol = requiredClass("scala.annotation.showAsInfix")
-  @tu lazy val StableAnnot: ClassSymbol = requiredClass("scala.annotation.internal.Stable")
   @tu lazy val FunctionalInterfaceAnnot: ClassSymbol = requiredClass("java.lang.FunctionalInterface")
   @tu lazy val TargetNameAnnot: ClassSymbol = requiredClass("scala.annotation.targetName")
   @tu lazy val VarargsAnnot: ClassSymbol = requiredClass("scala.annotation.varargs")
diff --git a/compiler/src/dotty/tools/dotc/core/Types.scala b/compiler/src/dotty/tools/dotc/core/Types.scala
index 842bd3b403e2..684b8faa13ea 100644
--- a/compiler/src/dotty/tools/dotc/core/Types.scala
+++ b/compiler/src/dotty/tools/dotc/core/Types.scala
@@ -168,7 +168,11 @@ object Types {
       case _: SingletonType | NoPrefix => true
       case tp: RefinedOrRecType => tp.parent.isStable
       case tp: ExprType => tp.resultType.isStable
-      case tp: AnnotatedType => tp.annot.symbol == defn.StableAnnot || tp.parent.isStable
+      case tp: AnnotatedType =>
+        // NOTE UncheckedStableAnnot was originally meant to be put on fields,
+        // not on types. Allowing it on types is a Scala 3 extension. See:
+        // https://www.scala-lang.org/files/archive/spec/2.11/11-annotations.html#scala-compiler-annotations
+        tp.annot.symbol == defn.UncheckedStableAnnot || tp.parent.isStable
       case tp: AndType =>
         // TODO: fix And type check when tp contains type parames for explicit-nulls flow-typing
         // see: tests/explicit-nulls/pos/flow-stable.scala.disabled
diff --git a/compiler/src/dotty/tools/dotc/typer/Typer.scala b/compiler/src/dotty/tools/dotc/typer/Typer.scala
index 0c7867a03bdc..98934734aae3 100644
--- a/compiler/src/dotty/tools/dotc/typer/Typer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Typer.scala
@@ -3539,7 +3539,7 @@ class Typer extends Namer
                   // this is needed for -Ycheck. Without the annotation Ycheck will
                   // skolemize the result type which will lead to different types before
                   // and after checking. See i11955.scala.
-                  AnnotatedType(conj, Annotation(defn.StableAnnot))
+                  AnnotatedType(conj, Annotation(defn.UncheckedStableAnnot))
                 else conj
               else pt
             gadts.println(i"insert GADT cast from $tree to $target")
diff --git a/library/src/scala/annotation/internal/Stable.scala b/library/src/scala/annotation/internal/Stable.scala
deleted file mode 100644
index bb53701716b5..000000000000
--- a/library/src/scala/annotation/internal/Stable.scala
+++ /dev/null
@@ -1,6 +0,0 @@
-package scala.annotation.internal
-
-import scala.annotation.Annotation
-
-/** An annotation asserting that the annotated type is stable */
-final class Stable() extends Annotation