diff --git a/src/Trait.ts b/src/Trait.ts
index c049304..1612d03 100644
--- a/src/Trait.ts
+++ b/src/Trait.ts
@@ -14,7 +14,9 @@ export type AddAbstractToImplClass<
     StaticAbstract extends {},
 > = (
     Class<
-        Abstract & InstanceType<ImplClass>,
+        Abstract &
+        InstanceType<ImplClass>,
+
         ConstructorParameters<ImplClass>
     > &
     StaticAbstract &
@@ -22,7 +24,7 @@ export type AddAbstractToImplClass<
 )
 
 export type RemoveAbstractFromImplClass<
-    ImplClassWithAbstract extends Class<Abstract, []> & { _tag: TraitApplierSuperTag },
+    ImplClassWithAbstract extends Class<Abstract, []> & StaticAbstract & { _tag: TraitApplierSuperTag },
     Abstract              extends {},
     StaticAbstract        extends {},
 > = (
@@ -153,11 +155,11 @@ export namespace Trait {
 export function trait<
     Abstract              extends {},
     StaticAbstract        extends {},
-    ImplClassWithAbstract extends Class<Abstract, []> & { _tag: TraitApplierSuperTag },
+    ImplClassWithAbstract extends Class<Abstract, []> & StaticAbstract & { _tag: TraitApplierSuperTag },
 >(
     abstract:        Opaque<Abstract, AbstractTag>,
     staticAbstract:  Opaque<StaticAbstract, AbstractTag>,
-    apply:           (Super: AbstractClass<Abstract> & { _tag: TraitApplierSuperTag }) => ImplClassWithAbstract,
+    apply:           (Super: AbstractClass<Abstract> & StaticAbstract & { _tag: TraitApplierSuperTag }) => ImplClassWithAbstract,
 ) {
     return new Trait(
         emptyTraitExpression,
diff --git a/src/TraitExpression.ts b/src/TraitExpression.ts
index 0c0f0f0..d3ea079 100644
--- a/src/TraitExpression.ts
+++ b/src/TraitExpression.ts
@@ -55,7 +55,7 @@ export class TraitExpression<
         This                          extends TraitExpression<typeof TraitExpression.NullSuperclass, any, any>,
         SubtraitAbstract              extends Implements<This>,
         SubtraitStaticAbstract        extends ImplementsStatic<This>,
-        SubtraitImplClassWithAbstract extends Class<SubtraitAbstract, []> & { _tag: TraitApplierSuperTag },
+        SubtraitImplClassWithAbstract extends Class<SubtraitAbstract, []> & SubtraitStaticAbstract & { _tag: TraitApplierSuperTag },
     >(
         this:            This,
         abstract:        (expression: This) => Opaque<SubtraitAbstract, AbstractTag>,