diff --git a/d2ast/d2ast.go b/d2ast/d2ast.go
index 3d209be6a..9562cad13 100644
--- a/d2ast/d2ast.go
+++ b/d2ast/d2ast.go
@@ -650,9 +650,14 @@ func (mk1 *Key) Equals(mk2 *Key) bool {
 	}
 
 	if mk1.Value.Unbox() != nil {
-		if mk1.Value.ScalarBox().Unbox().ScalarString() != mk2.Value.ScalarBox().Unbox().ScalarString() {
+		if (mk1.Value.ScalarBox().Unbox() == nil) != (mk2.Value.ScalarBox().Unbox() == nil) {
 			return false
 		}
+		if mk1.Value.ScalarBox().Unbox() != nil {
+			if mk1.Value.ScalarBox().Unbox().ScalarString() != mk2.Value.ScalarBox().Unbox().ScalarString() {
+				return false
+			}
+		}
 	}
 
 	return true
diff --git a/d2oracle/edit_test.go b/d2oracle/edit_test.go
index 3f10dfe4a..0d1e27f36 100644
--- a/d2oracle/edit_test.go
+++ b/d2oracle/edit_test.go
@@ -1858,6 +1858,32 @@ func TestMove(t *testing.T) {
 				assert.JSON(t, g.Objects[1].ID, "c")
 			},
 		},
+		{
+			name: "duplicate",
+
+			text: `a: {
+  b: {
+    shape: cylinder
+  }
+}
+
+a: {
+  b: {
+    shape: cylinder
+  }
+}
+`,
+			key:    `a.b`,
+			newKey: `b`,
+
+			exp: `a
+
+a
+b: {
+  shape: cylinder
+}
+`,
+		},
 		{
 			name: "rename_2",
 
diff --git a/testdata/d2oracle/TestMove/duplicate.exp.json b/testdata/d2oracle/TestMove/duplicate.exp.json
new file mode 100644
index 000000000..9364aa80e
--- /dev/null
+++ b/testdata/d2oracle/TestMove/duplicate.exp.json
@@ -0,0 +1,262 @@
+{
+  "graph": {
+    "name": "",
+    "isFolderOnly": false,
+    "ast": {
+      "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,0:0:0-6:0:30",
+      "nodes": [
+        {
+          "map_key": {
+            "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,0:0:0-0:1:1",
+            "key": {
+              "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,0:0:0-0:1:1",
+              "path": [
+                {
+                  "unquoted_string": {
+                    "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,0:0:0-0:1:1",
+                    "value": [
+                      {
+                        "string": "a",
+                        "raw_string": "a"
+                      }
+                    ]
+                  }
+                }
+              ]
+            },
+            "primary": {},
+            "value": {}
+          }
+        },
+        {
+          "map_key": {
+            "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,2:0:3-2:1:4",
+            "key": {
+              "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,2:0:3-2:1:4",
+              "path": [
+                {
+                  "unquoted_string": {
+                    "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,2:0:3-2:1:4",
+                    "value": [
+                      {
+                        "string": "a",
+                        "raw_string": "a"
+                      }
+                    ]
+                  }
+                }
+              ]
+            },
+            "primary": {},
+            "value": {}
+          }
+        },
+        {
+          "map_key": {
+            "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,3:0:5-5:1:29",
+            "key": {
+              "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,3:0:5-3:1:6",
+              "path": [
+                {
+                  "unquoted_string": {
+                    "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,3:0:5-3:1:6",
+                    "value": [
+                      {
+                        "string": "b",
+                        "raw_string": "b"
+                      }
+                    ]
+                  }
+                }
+              ]
+            },
+            "primary": {},
+            "value": {
+              "map": {
+                "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,3:3:8-5:0:28",
+                "nodes": [
+                  {
+                    "map_key": {
+                      "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,4:2:12-4:17:27",
+                      "key": {
+                        "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,4:2:12-4:7:17",
+                        "path": [
+                          {
+                            "unquoted_string": {
+                              "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,4:2:12-4:7:17",
+                              "value": [
+                                {
+                                  "string": "shape",
+                                  "raw_string": "shape"
+                                }
+                              ]
+                            }
+                          }
+                        ]
+                      },
+                      "primary": {},
+                      "value": {
+                        "unquoted_string": {
+                          "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,4:9:19-4:17:27",
+                          "value": [
+                            {
+                              "string": "cylinder",
+                              "raw_string": "cylinder"
+                            }
+                          ]
+                        }
+                      }
+                    }
+                  }
+                ]
+              }
+            }
+          }
+        }
+      ]
+    },
+    "root": {
+      "id": "",
+      "id_val": "",
+      "label_dimensions": {
+        "width": 0,
+        "height": 0
+      },
+      "attributes": {
+        "label": {
+          "value": ""
+        },
+        "style": {},
+        "near_key": null,
+        "shape": {
+          "value": ""
+        },
+        "direction": {
+          "value": ""
+        },
+        "constraint": {
+          "value": ""
+        }
+      },
+      "zIndex": 0
+    },
+    "edges": null,
+    "objects": [
+      {
+        "id": "a",
+        "id_val": "a",
+        "label_dimensions": {
+          "width": 0,
+          "height": 0
+        },
+        "references": [
+          {
+            "key": {
+              "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,0:0:0-0:1:1",
+              "path": [
+                {
+                  "unquoted_string": {
+                    "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,0:0:0-0:1:1",
+                    "value": [
+                      {
+                        "string": "a",
+                        "raw_string": "a"
+                      }
+                    ]
+                  }
+                }
+              ]
+            },
+            "key_path_index": 0,
+            "map_key_edge_index": -1
+          },
+          {
+            "key": {
+              "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,2:0:3-2:1:4",
+              "path": [
+                {
+                  "unquoted_string": {
+                    "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,2:0:3-2:1:4",
+                    "value": [
+                      {
+                        "string": "a",
+                        "raw_string": "a"
+                      }
+                    ]
+                  }
+                }
+              ]
+            },
+            "key_path_index": 0,
+            "map_key_edge_index": -1
+          }
+        ],
+        "attributes": {
+          "label": {
+            "value": "a"
+          },
+          "style": {},
+          "near_key": null,
+          "shape": {
+            "value": "rectangle"
+          },
+          "direction": {
+            "value": ""
+          },
+          "constraint": {
+            "value": ""
+          }
+        },
+        "zIndex": 0
+      },
+      {
+        "id": "b",
+        "id_val": "b",
+        "label_dimensions": {
+          "width": 0,
+          "height": 0
+        },
+        "references": [
+          {
+            "key": {
+              "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,3:0:5-3:1:6",
+              "path": [
+                {
+                  "unquoted_string": {
+                    "range": "d2/testdata/d2oracle/TestMove/duplicate.d2,3:0:5-3:1:6",
+                    "value": [
+                      {
+                        "string": "b",
+                        "raw_string": "b"
+                      }
+                    ]
+                  }
+                }
+              ]
+            },
+            "key_path_index": 0,
+            "map_key_edge_index": -1
+          }
+        ],
+        "attributes": {
+          "label": {
+            "value": "b"
+          },
+          "style": {},
+          "near_key": null,
+          "shape": {
+            "value": "cylinder"
+          },
+          "direction": {
+            "value": ""
+          },
+          "constraint": {
+            "value": ""
+          }
+        },
+        "zIndex": 0
+      }
+    ]
+  },
+  "err": "<nil>"
+}