diff --git a/src/core/interface.scala b/src/core/interface.scala
index 5c1c32a2..2f6093f5 100644
--- a/src/core/interface.scala
+++ b/src/core/interface.scala
@@ -35,6 +35,7 @@ abstract class CaseClass[Typeclass[_], Type]
                         (val typeInfo: TypeInfo,
                          val isObject: Boolean,
                          val isValueClass: Boolean,
+                         val isOpaqueType: Boolean,
                          val params: IArray[CaseClass.Param[Typeclass, Type]],
                          val annotations: IArray[Any],
                          val typeAnnotations: IArray[Any]) extends Serializable:
diff --git a/src/core/macro.scala b/src/core/macro.scala
index 4abc76c3..44d74afc 100644
--- a/src/core/macro.scala
+++ b/src/core/macro.scala
@@ -5,6 +5,7 @@ import scala.quoted.*
 object Macro:
   inline def isObject[T]: Boolean = ${isObject[T]}
   inline def isEnum[T]: Boolean = ${isEnum[T]}
+  inline def isOpaqueType[T]: Boolean = ${isOpaqueType[T]}
   inline def anns[T]: List[Any] = ${anns[T]}
   inline def typeAnns[T]: List[Any] = ${typeAnns[T]}
   inline def paramAnns[T]: List[(String, List[Any])] = ${paramAnns[T]}
@@ -30,6 +31,11 @@ object Macro:
 
     Expr(TypeRepr.of[T].typeSymbol.flags.is(Flags.Enum))
 
+  def isOpaqueType[T: Type](using Quotes): Expr[Boolean] =
+    import quotes.reflect.*
+
+    Expr(TypeRepr.of[T].typeSymbol.flags.is(Flags.Opaque))
+
   def paramAnns[T: Type](using Quotes): Expr[List[(String, List[Any])]] =
     import quotes.reflect.*
 
diff --git a/src/core/magnolia.scala b/src/core/magnolia.scala
index 4d68bb64..319df33e 100644
--- a/src/core/magnolia.scala
+++ b/src/core/magnolia.scala
@@ -13,7 +13,7 @@ trait CommonDerivation[TypeClass[_]]:
     val parameters = IArray(getParams[A, product.MirroredElemLabels, product.MirroredElemTypes](
         paramAnns[A].to(Map), paramTypeAnns[A].to(Map), repeated[A].to(Map))*)
     
-    val caseClass = new CaseClass[Typeclass, A](typeInfo[A], isObject[A], isValueClass[A], parameters,
+    val caseClass = new CaseClass[Typeclass, A](typeInfo[A], isObject[A], isValueClass[A], isOpaqueType[A], parameters,
         IArray(anns[A]*), IArray[Any](typeAnns[A]*)):
       
       def construct[PType](makeParam: Param => PType)(using ClassTag[PType]): A =