diff --git a/libs/binder/ndk/ibinder.cpp b/libs/binder/ndk/ibinder.cpp
index b8c4878..22ce8fe 100644
--- a/libs/binder/ndk/ibinder.cpp
+++ b/libs/binder/ndk/ibinder.cpp
@@ -301,6 +301,26 @@
     return binder.get();
 }
 
+AIBinder_Weak* AIBinder_Weak_clone(const AIBinder_Weak* weak) {
+    if (weak == nullptr) {
+        return nullptr;
+    }
+
+    return new AIBinder_Weak{weak->binder};
+}
+
+bool AIBinder_lt(const AIBinder* lhs, const AIBinder* rhs) {
+    if (lhs == nullptr || rhs == nullptr) return lhs < rhs;
+
+    return const_cast<AIBinder*>(lhs)->getBinder() < const_cast<AIBinder*>(rhs)->getBinder();
+}
+
+bool AIBinder_Weak_lt(const AIBinder_Weak* lhs, const AIBinder_Weak* rhs) {
+    if (lhs == nullptr || rhs == nullptr) return lhs < rhs;
+
+    return lhs->binder < rhs->binder;
+}
+
 AIBinder_Class::AIBinder_Class(const char* interfaceDescriptor, AIBinder_Class_onCreate onCreate,
                                AIBinder_Class_onDestroy onDestroy,
                                AIBinder_Class_onTransact onTransact)
diff --git a/libs/binder/ndk/include_ndk/android/binder_ibinder.h b/libs/binder/ndk/include_ndk/android/binder_ibinder.h
index 5e1ed46..0ca3a07 100644
--- a/libs/binder/ndk/include_ndk/android/binder_ibinder.h
+++ b/libs/binder/ndk/include_ndk/android/binder_ibinder.h
@@ -657,6 +657,68 @@
  */
 const char* AIBinder_Class_getDescriptor(const AIBinder_Class* clazz) __INTRODUCED_IN(31);
 
+/**
+ * Whether AIBinder is less than another.
+ *
+ * This provides a per-process-unique total ordering of binders determined by
+ * an underlying allocation address where a null AIBinder* is considered to be
+ * ordered before all other binders.
+ *
+ * AIBinder* pointers themselves actually also create a per-process-unique total
+ * ordering. However, this ordering is inconsistent with AIBinder_Weak_lt for
+ * remote binders.
+ *
+ * Available since API level 31.
+ *
+ * \param lhs comparison object
+ * \param rhs comparison object
+ *
+ * \return whether "lhs < rhs" is true
+ */
+bool AIBinder_lt(const AIBinder* lhs, const AIBinder* rhs);
+
+/**
+ * Clone an AIBinder_Weak. Useful because even if a weak binder promotes to a
+ * null value, after further binder transactions, it may no longer promote to a
+ * null value.
+ *
+ * Available since API level 31.
+ *
+ * \param weak Object to clone
+ *
+ * \return clone of the input parameter. This must be deleted with
+ * AIBinder_Weak_delete. Null if weak input parameter is also null.
+ */
+AIBinder_Weak* AIBinder_Weak_clone(const AIBinder_Weak* weak);
+
+/**
+ * Whether AIBinder_Weak is less than another.
+ *
+ * This provides a per-process-unique total ordering of binders which is exactly
+ * the same as AIBinder_lt. Similarly, a null AIBinder_Weak* is considered to be
+ * ordered before all other weak references.
+ *
+ * If you have many AIBinder_Weak* objects which are all references to distinct
+ * binder objects which happen to have the same underlying address (as ordered
+ * by AIBinder_lt), these AIBinder_Weak* objects will retain the same order with
+ * respect to all other AIBinder_Weak* pointers with different underlying
+ * addresses and are also guaranteed to have a per-process-unique ordering. That
+ * is, even though multiple AIBinder* instances may happen to be allocated at
+ * the same underlying address, this function will still correctly distinguish
+ * that these are weak pointers to different binder objects.
+ *
+ * Unlike AIBinder*, the AIBinder_Weak* addresses themselves have nothing to do
+ * with the underlying binder.
+ *
+ * Available since API level 31.
+ *
+ * \param lhs comparison object
+ * \param rhs comparison object
+ *
+ * \return whether "lhs < rhs" is true
+ */
+bool AIBinder_Weak_lt(const AIBinder_Weak* lhs, const AIBinder_Weak* rhs);
+
 #endif  //__ANDROID_API__ >= 31
 
 __END_DECLS
diff --git a/libs/binder/ndk/libbinder_ndk.map.txt b/libs/binder/ndk/libbinder_ndk.map.txt
index e233ffd..9a93bf3 100644
--- a/libs/binder/ndk/libbinder_ndk.map.txt
+++ b/libs/binder/ndk/libbinder_ndk.map.txt
@@ -122,6 +122,9 @@
     AServiceManager_waitForService; # apex llndk
 
     AIBinder_Class_getDescriptor;
+    AIBinder_Weak_clone;
+    AIBinder_Weak_lt;
+    AIBinder_lt;
     AParcel_appendFrom;
     AParcel_create;
     AParcel_getDataSize;