diff --git a/src/lua.rs b/src/lua.rs
index 0c65c88..9c773b8 100644
--- a/src/lua.rs
+++ b/src/lua.rs
@@ -2444,7 +2444,6 @@ impl<'lua, T: 'static + UserData> UserDataMethods<'lua, T> for StaticUserDataMet
     #[cfg(feature = "async")]
     fn add_async_function<S, A, R, F, FR>(&mut self, name: &S, function: F)
     where
-        T: Clone,
         S: AsRef<[u8]> + ?Sized,
         A: FromLuaMulti<'lua>,
         R: ToLuaMulti<'lua>,
diff --git a/src/scope.rs b/src/scope.rs
index fa5bcc2..ad9e90d 100644
--- a/src/scope.rs
+++ b/src/scope.rs
@@ -663,7 +663,6 @@ impl<'lua, T: UserData> UserDataMethods<'lua, T> for NonStaticUserDataMethods<'l
     #[cfg(feature = "async")]
     fn add_async_function<S, A, R, F, FR>(&mut self, _name: &S, _function: F)
     where
-        T: Clone,
         S: AsRef<[u8]> + ?Sized,
         A: FromLuaMulti<'lua>,
         R: ToLuaMulti<'lua>,
diff --git a/src/userdata.rs b/src/userdata.rs
index 1decf1a..d9e75d3 100644
--- a/src/userdata.rs
+++ b/src/userdata.rs
@@ -359,7 +359,6 @@ pub trait UserDataMethods<'lua, T: UserData> {
     #[cfg_attr(docsrs, doc(cfg(feature = "async")))]
     fn add_async_function<S, A, R, F, FR>(&mut self, name: &S, function: F)
     where
-        T: Clone,
         S: AsRef<[u8]> + ?Sized,
         A: FromLuaMulti<'lua>,
         R: ToLuaMulti<'lua>,