diff --git a/src/main/java/tools/jackson/databind/deser/jdk/UntypedObjectDeserializerNR.java b/src/main/java/tools/jackson/databind/deser/jdk/UntypedObjectDeserializerNR.java
index 336ba05c6d..cb3155908d 100644
--- a/src/main/java/tools/jackson/databind/deser/jdk/UntypedObjectDeserializerNR.java
+++ b/src/main/java/tools/jackson/databind/deser/jdk/UntypedObjectDeserializerNR.java
@@ -353,48 +353,6 @@ protected Object _deserializeFP(JsonParser p, DeserializationContext ctxt)
         }
         return p.getDoubleValue();
     }
-    
-    // NOTE: copied from above (alas, no easy way to share/reuse)
-    // @since 2.12 (wrt [databind#2733]
-    protected Object _mapObjectWithDups(JsonParser p, DeserializationContext ctxt,
-            final Map<String, Object> result, String initialKey,
-            Object oldValue, Object newValue, String nextKey)
-        throws JacksonException
-    {
-        final boolean squashDups = ctxt.isEnabled(StreamReadCapability.DUPLICATE_PROPERTIES);
-
-        if (squashDups) {
-            _squashDups(result, initialKey, oldValue, newValue);
-        }
-
-        while (nextKey != null) {
-            p.nextToken();
-            newValue = deserialize(p, ctxt);
-            oldValue = result.put(nextKey, newValue);
-            if ((oldValue != null) && squashDups) {
-                _squashDups(result, nextKey, oldValue, newValue);
-            }
-            nextKey = p.nextName();
-        }
-
-        return result;
-    }
-
-    // NOTE: copied from above (alas, no easy way to share/reuse)
-    @SuppressWarnings("unchecked")
-    private void _squashDups(final Map<String, Object> result, String key,
-            Object oldValue, Object newValue)
-    {
-        if (oldValue instanceof List<?>) {
-            ((List<Object>) oldValue).add(newValue);
-            result.put(key, oldValue);
-        } else {
-            ArrayList<Object> l = new ArrayList<>();
-            l.add(oldValue);
-            l.add(newValue);
-            result.put(key, l);
-        }
-    }
 
     /*
     /**********************************************************************
diff --git a/src/test/java/tools/jackson/databind/interop/UntypedObjectWithDupsTest.java b/src/test/java/tools/jackson/databind/interop/UntypedObjectWithDupsTest.java
index 8fb0716296..4e11f4b984 100644
--- a/src/test/java/tools/jackson/databind/interop/UntypedObjectWithDupsTest.java
+++ b/src/test/java/tools/jackson/databind/interop/UntypedObjectWithDupsTest.java
@@ -24,13 +24,15 @@ static class StringStringMap extends LinkedHashMap<String,String> { };
     private final String DOC_WITH_DUPS = a2q(
             "{'hello': 'world',\n"
             + "'lists' : 1,\n"
-            + "'lists' : 2,\n"
+            + "'lists' : 2.5,\n"
             + "'lists' : {\n"
             + "  'inner' : 'internal',\n"
             + "  'time' : 123\n"
             + "},\n"
-            + "'lists' : 3,\n"
-            + "'single' : 'one'\n"
+            + "'lists' : true,\n"
+            + "'single' : 'one',\n"
+            + "'lists' : false,\n"
+            + "'lists' : null\n"
             + "}");
 
     // Testing the baseline non-merging behavior
@@ -84,7 +86,7 @@ private <T> void _verifyDupsNoMerging(Class<T> cls) throws Exception
 
         String json = JSON_MAPPER.writeValueAsString(value);
         assertEquals(a2q(
-"{'hello':'world','lists':3,'single':'one'}"),
+"{'hello':'world','lists':null,'single':'one'}"),
                 json);
     }
 
@@ -94,8 +96,8 @@ private <T> void _verifyDupsNoMerging(Class<T> cls) throws Exception
     private void _verifyDupsAreMerged(Class<?> cls) throws Exception
     {
         assertEquals(a2q(
-"{'hello':'world','lists':[1,2,"
-+"{'inner':'internal','time':123},3],'single':'one'}"),
+"{'hello':'world','lists':[1,2.5,"
++"{'inner':'internal','time':123},true,false,null],'single':'one'}"),
                 _readWriteDupDoc(DOC_WITH_DUPS, cls));
     }