diff --git a/neuralnetworks/aidl/utils/include/nnapi/hal/aidl/Callbacks.h b/neuralnetworks/aidl/utils/include/nnapi/hal/aidl/Callbacks.h
index 8651912..168264b 100644
--- a/neuralnetworks/aidl/utils/include/nnapi/hal/aidl/Callbacks.h
+++ b/neuralnetworks/aidl/utils/include/nnapi/hal/aidl/Callbacks.h
@@ -32,8 +32,7 @@
 namespace aidl::android::hardware::neuralnetworks::utils {
 
 // An AIDL callback class to receive the results of IDevice::prepareModel* asynchronously.
-class PreparedModelCallback final : public BnPreparedModelCallback,
-                                    public hal::utils::IProtectedCallback {
+class PreparedModelCallback final : public BnPreparedModelCallback, public IProtectedCallback {
   public:
     using Data = nn::GeneralResult<nn::SharedPreparedModel>;
 
diff --git a/neuralnetworks/aidl/utils/include/nnapi/hal/aidl/ProtectCallback.h b/neuralnetworks/aidl/utils/include/nnapi/hal/aidl/ProtectCallback.h
index ab1108c..92ed1cd 100644
--- a/neuralnetworks/aidl/utils/include/nnapi/hal/aidl/ProtectCallback.h
+++ b/neuralnetworks/aidl/utils/include/nnapi/hal/aidl/ProtectCallback.h
@@ -23,7 +23,6 @@
 #include <nnapi/Result.h>
 #include <nnapi/Types.h>
 #include <nnapi/hal/CommonUtils.h>
-#include <nnapi/hal/ProtectCallback.h>
 
 #include <functional>
 #include <mutex>
@@ -34,19 +33,39 @@
 
 namespace aidl::android::hardware::neuralnetworks::utils {
 
+class IProtectedCallback {
+  public:
+    /**
+     * Marks this object as a dead object.
+     */
+    virtual void notifyAsDeadObject() = 0;
+
+    // Public virtual destructor to allow objects to be stored (and destroyed) as smart pointers.
+    // E.g., std::unique_ptr<IProtectedCallback>.
+    virtual ~IProtectedCallback() = default;
+
+  protected:
+    // Protect the non-destructor special member functions to prevent object slicing.
+    IProtectedCallback() = default;
+    IProtectedCallback(const IProtectedCallback&) = default;
+    IProtectedCallback(IProtectedCallback&&) noexcept = default;
+    IProtectedCallback& operator=(const IProtectedCallback&) = default;
+    IProtectedCallback& operator=(IProtectedCallback&&) noexcept = default;
+};
+
 // Thread safe class
 class DeathMonitor final {
   public:
     static void serviceDied(void* cookie);
     void serviceDied();
     // Precondition: `killable` must be non-null.
-    void add(hal::utils::IProtectedCallback* killable) const;
+    void add(IProtectedCallback* killable) const;
     // Precondition: `killable` must be non-null.
-    void remove(hal::utils::IProtectedCallback* killable) const;
+    void remove(IProtectedCallback* killable) const;
 
   private:
     mutable std::mutex mMutex;
-    mutable std::vector<hal::utils::IProtectedCallback*> mObjects GUARDED_BY(mMutex);
+    mutable std::vector<IProtectedCallback*> mObjects GUARDED_BY(mMutex);
 };
 
 class DeathHandler final {
@@ -62,7 +81,7 @@
     using Cleanup = std::function<void()>;
     // Precondition: `killable` must be non-null.
     [[nodiscard]] ::android::base::ScopeGuard<Cleanup> protectCallback(
-            hal::utils::IProtectedCallback* killable) const;
+            IProtectedCallback* killable) const;
 
     std::shared_ptr<DeathMonitor> getDeathMonitor() const { return kDeathMonitor; }
 
diff --git a/neuralnetworks/aidl/utils/src/ProtectCallback.cpp b/neuralnetworks/aidl/utils/src/ProtectCallback.cpp
index 124641c..54a673c 100644
--- a/neuralnetworks/aidl/utils/src/ProtectCallback.cpp
+++ b/neuralnetworks/aidl/utils/src/ProtectCallback.cpp
@@ -22,7 +22,6 @@
 #include <android/binder_auto_utils.h>
 #include <android/binder_interface_utils.h>
 #include <nnapi/Result.h>
-#include <nnapi/hal/ProtectCallback.h>
 
 #include <algorithm>
 #include <functional>
@@ -37,7 +36,7 @@
 void DeathMonitor::serviceDied() {
     std::lock_guard guard(mMutex);
     std::for_each(mObjects.begin(), mObjects.end(),
-                  [](hal::utils::IProtectedCallback* killable) { killable->notifyAsDeadObject(); });
+                  [](IProtectedCallback* killable) { killable->notifyAsDeadObject(); });
 }
 
 void DeathMonitor::serviceDied(void* cookie) {
@@ -45,13 +44,13 @@
     deathMonitor->serviceDied();
 }
 
-void DeathMonitor::add(hal::utils::IProtectedCallback* killable) const {
+void DeathMonitor::add(IProtectedCallback* killable) const {
     CHECK(killable != nullptr);
     std::lock_guard guard(mMutex);
     mObjects.push_back(killable);
 }
 
-void DeathMonitor::remove(hal::utils::IProtectedCallback* killable) const {
+void DeathMonitor::remove(IProtectedCallback* killable) const {
     CHECK(killable != nullptr);
     std::lock_guard guard(mMutex);
     const auto removedIter = std::remove(mObjects.begin(), mObjects.end(), killable);
@@ -102,7 +101,7 @@
 }
 
 [[nodiscard]] ::android::base::ScopeGuard<DeathHandler::Cleanup> DeathHandler::protectCallback(
-        hal::utils::IProtectedCallback* killable) const {
+        IProtectedCallback* killable) const {
     CHECK(killable != nullptr);
     kDeathMonitor->add(killable);
     return ::android::base::make_scope_guard(