diff --git a/src/core/hle/service/cmif_serialization.h b/src/core/hle/service/cmif_serialization.h
index 315475e71b..e985fe3170 100644
--- a/src/core/hle/service/cmif_serialization.h
+++ b/src/core/hle/service/cmif_serialization.h
@@ -115,6 +115,11 @@ struct ArgumentTraits {
     static constexpr ArgumentType Type = ArgumentType::InData;
 };
 
+template <typename... Ts>
+consteval bool ConstIfReference() {
+    return ((!std::is_reference_v<Ts> || std::is_const_v<std::remove_reference_t<Ts>>) && ... && true);
+}
+
 struct RequestLayout {
     u32 copy_handle_count;
     u32 move_handle_count;
@@ -435,6 +440,7 @@ void CmifReplyWrapImpl(HLERequestContext& ctx, T& t, Result (T::*f)(A...)) {
     }
     const bool is_domain = Domain ? ctx.GetManager()->IsDomain() : false;
 
+    static_assert(ConstIfReference<A...>(), "Arguments taken by reference must be const");
     using MethodArguments = std::tuple<std::remove_cvref_t<A>...>;
 
     OutTemporaryBuffers buffers{};
diff --git a/src/core/hle/service/cmif_types.h b/src/core/hle/service/cmif_types.h
index dc06169f44..84f4c2456a 100644
--- a/src/core/hle/service/cmif_types.h
+++ b/src/core/hle/service/cmif_types.h
@@ -4,10 +4,9 @@
 #pragma once
 
 #include <memory>
+#include <span>
 
-#include "common/common_funcs.h"
 #include "common/common_types.h"
-#include "core/hle/service/hle_ipc.h"
 
 namespace Service {
 
@@ -22,8 +21,10 @@ class Out {
 public:
     using Type = T;
 
+    /* implicit */ Out(const Out& t) : raw(t.raw) {}
     /* implicit */ Out(AutoOut<Type>& t) : raw(&t.raw) {}
     /* implicit */ Out(Type* t) : raw(t) {}
+    Out& operator=(const Out&) = delete;
 
     Type* Get() const {
         return raw;
@@ -37,6 +38,10 @@ public:
         return raw;
     }
 
+    operator Type*() const {
+        return raw;
+    }
+
 private:
     Type* raw;
 };
@@ -113,8 +118,10 @@ class OutCopyHandle {
 public:
     using Type = T*;
 
+    /* implicit */ OutCopyHandle(const OutCopyHandle& t) : raw(t.raw) {}
     /* implicit */ OutCopyHandle(AutoOut<Type>& t) : raw(&t.raw) {}
     /* implicit */ OutCopyHandle(Type* t) : raw(t) {}
+    OutCopyHandle& operator=(const OutCopyHandle&) = delete;
 
     Type* Get() const {
         return raw;
@@ -128,6 +135,10 @@ public:
         return raw;
     }
 
+    operator Type*() const {
+        return raw;
+    }
+
 private:
     Type* raw;
 };
@@ -137,8 +148,10 @@ class OutMoveHandle {
 public:
     using Type = T*;
 
+    /* implicit */ OutMoveHandle(const OutMoveHandle& t) : raw(t.raw) {}
     /* implicit */ OutMoveHandle(AutoOut<Type>& t) : raw(&t.raw) {}
     /* implicit */ OutMoveHandle(Type* t) : raw(t) {}
+    OutMoveHandle& operator=(const OutMoveHandle&) = delete;
 
     Type* Get() const {
         return raw;
@@ -152,6 +165,10 @@ public:
         return raw;
     }
 
+    operator Type*() const {
+        return raw;
+    }
+
 private:
     Type* raw;
 };
@@ -248,8 +265,10 @@ public:
     static constexpr BufferAttr Attr = static_cast<BufferAttr>(A | BufferAttr_In | BufferAttr_FixedSize);
     using Type = T;
 
+    /* implicit */ OutLargeData(const OutLargeData& t) : raw(t.raw) {}
     /* implicit */ OutLargeData(Type* t) : raw(t) {}
     /* implicit */ OutLargeData(AutoOut<T>& t) : raw(&t.raw) {}
+    OutLargeData& operator=(const OutLargeData&) = delete;
 
     Type* Get() const {
         return raw;
@@ -263,6 +282,10 @@ public:
         return raw;
     }
 
+    operator Type*() const {
+        return raw;
+    }
+
 private:
     Type* raw;
 };