diff --git a/dm_control/mjcf/schema.xml b/dm_control/mjcf/schema.xml
index cf376fa8..d9c13bd1 100644
--- a/dm_control/mjcf/schema.xml
+++ b/dm_control/mjcf/schema.xml
@@ -2193,7 +2193,7 @@
             <attribute name="armature" type="float"/>
             <attribute name="cranklength" type="float"/>
             <attribute name="joint" type="reference" reference_namespace="joint"/>
-            <attribute name="jointinparent" type="string"/>
+            <attribute name="jointinparent" type="reference" reference_namespace="joint"/>
             <attribute name="tendon" type="reference" reference_namespace="tendon"/>
             <attribute name="slidersite" type="reference" reference_namespace="site"/>
             <attribute name="cranksite" type="reference" reference_namespace="site"/>
@@ -2232,7 +2232,7 @@
             <attribute name="armature" type="float"/>
             <attribute name="cranklength" type="float"/>
             <attribute name="joint" type="reference" reference_namespace="joint"/>
-            <attribute name="jointinparent" type="string"/>
+            <attribute name="jointinparent" type="reference" reference_namespace="joint"/>
             <attribute name="tendon" type="reference" reference_namespace="tendon"/>
             <attribute name="slidersite" type="reference" reference_namespace="site"/>
             <attribute name="cranksite" type="reference" reference_namespace="site"/>
@@ -2260,7 +2260,7 @@
             <attribute name="armature" type="float"/>
             <attribute name="cranklength" type="float"/>
             <attribute name="joint" type="reference" reference_namespace="joint"/>
-            <attribute name="jointinparent" type="string"/>
+            <attribute name="jointinparent" type="reference" reference_namespace="joint"/>
             <attribute name="tendon" type="reference" reference_namespace="tendon"/>
             <attribute name="slidersite" type="reference" reference_namespace="site"/>
             <attribute name="cranksite" type="reference" reference_namespace="site"/>
@@ -2291,7 +2291,7 @@
             <attribute name="armature" type="float"/>
             <attribute name="cranklength" type="float"/>
             <attribute name="joint" type="reference" reference_namespace="joint"/>
-            <attribute name="jointinparent" type="string"/>
+            <attribute name="jointinparent" type="reference" reference_namespace="joint"/>
             <attribute name="tendon" type="reference" reference_namespace="tendon"/>
             <attribute name="slidersite" type="reference" reference_namespace="site"/>
             <attribute name="cranksite" type="reference" reference_namespace="site"/>
@@ -2322,7 +2322,7 @@
             <attribute name="armature" type="float"/>
             <attribute name="cranklength" type="float"/>
             <attribute name="joint" type="reference" reference_namespace="joint"/>
-            <attribute name="jointinparent" type="string"/>
+            <attribute name="jointinparent" type="reference" reference_namespace="joint"/>
             <attribute name="tendon" type="reference" reference_namespace="tendon"/>
             <attribute name="slidersite" type="reference" reference_namespace="site"/>
             <attribute name="cranksite" type="reference" reference_namespace="site"/>
@@ -2372,7 +2372,7 @@
             <attribute name="armature" type="float"/>
             <attribute name="cranklength" type="float"/>
             <attribute name="joint" type="reference" reference_namespace="joint"/>
-            <attribute name="jointinparent" type="string"/>
+            <attribute name="jointinparent" type="reference" reference_namespace="joint"/>
             <attribute name="tendon" type="reference" reference_namespace="tendon"/>
             <attribute name="slidersite" type="reference" reference_namespace="site"/>
             <attribute name="cranksite" type="reference" reference_namespace="site"/>
@@ -2400,7 +2400,7 @@
             <attribute name="armature" type="float"/>
             <attribute name="cranklength" type="float"/>
             <attribute name="joint" type="reference" reference_namespace="joint"/>
-            <attribute name="jointinparent" type="string"/>
+            <attribute name="jointinparent" type="reference" reference_namespace="joint"/>
             <attribute name="tendon" type="reference" reference_namespace="tendon"/>
             <attribute name="slidersite" type="reference" reference_namespace="site"/>
             <attribute name="cranksite" type="reference" reference_namespace="site"/>
@@ -2431,7 +2431,7 @@
             <attribute name="armature" type="float"/>
             <attribute name="cranklength" type="float"/>
             <attribute name="joint" type="reference" reference_namespace="joint"/>
-            <attribute name="jointinparent" type="string"/>
+            <attribute name="jointinparent" type="reference" reference_namespace="joint"/>
             <attribute name="tendon" type="reference" reference_namespace="tendon"/>
             <attribute name="slidersite" type="reference" reference_namespace="site"/>
             <attribute name="cranksite" type="reference" reference_namespace="site"/>
@@ -2486,7 +2486,7 @@
             <attribute name="armature" type="float"/>
             <attribute name="cranklength" type="float"/>
             <attribute name="joint" type="reference" reference_namespace="joint"/>
-            <attribute name="jointinparent" type="string"/>
+            <attribute name="jointinparent" type="reference" reference_namespace="joint"/>
             <attribute name="site" type="reference" reference_namespace="site"/>
             <attribute name="actdim" type="int" default="-1"/>
             <attribute name="dyntype" type="keyword" valid_values="none integrator filter filterexact muscle dcmotor pid user" default="none"/>
@@ -3128,6 +3128,28 @@
             <attribute name="user" type="array" array_type="float"/>
           </attributes>
         </element>
+        <element name="contact" repeated="true" namespace="sensor">
+          <attributes>
+            <attribute name="name" type="identifier"/>
+            <attribute name="noise" type="float"/>
+            <attribute name="cutoff" type="float"/>
+            <attribute name="nsample" type="int"/>
+            <attribute name="interp" type="keyword" valid_values="zoh linear cubic"/>
+            <attribute name="delay" type="float"/>
+            <attribute name="interval" type="array" array_type="float" array_size="2"/>
+            <attribute name="user" type="array" array_type="float"/>
+            <attribute name="num" type="int"/>
+            <attribute name="data" type="string"/>
+            <attribute name="reduce" type="keyword" valid_values="none mindist maxforce netforce"/>
+            <attribute name="site" type="reference"/>
+            <attribute name="body1" type="reference" reference_namespace="body"/>
+            <attribute name="body2" type="reference" reference_namespace="body"/>
+            <attribute name="subtree1" type="reference" reference_namespace="body"/>
+            <attribute name="subtree2" type="reference" reference_namespace="body"/>
+            <attribute name="geom1" type="reference" reference_namespace="geom"/>
+            <attribute name="geom2" type="reference" reference_namespace="geom"/>
+          </attributes>
+        </element>
         <element name="tactile" repeated="true" namespace="sensor">
           <attributes>
             <attribute name="name" type="identifier"/>
@@ -3182,7 +3204,7 @@
           <attributes>
             <attribute name="name" type="identifier" required="true"/>
             <attribute name="size" type="int"/>
-            <attribute name="data" type="string"/>
+            <attribute name="data" type="array" array_type="float"/>
           </attributes>
         </element>
         <element name="text" repeated="true">
diff --git a/dm_control/mjcf/schema_test.py b/dm_control/mjcf/schema_test.py
index 1eda0e8c..6f52630d 100644
--- a/dm_control/mjcf/schema_test.py
+++ b/dm_control/mjcf/schema_test.py
@@ -187,5 +187,46 @@ def constructible(spec_node, path):
                 + '\n'.join(failures[:20]))
 
 
+class SchemaRegressionTest(absltest.TestCase):
+  """Declarations that MuJoCo accepts must stay representable in PyMJCF."""
+
+  def test_contact_sensor_parses_and_compiles(self):
+    xml_string = """
+      <mujoco>
+        <worldbody>
+          <body name="b">
+            <joint name="j" type="slide"/>
+            <geom name="g" size="0.1"/>
+          </body>
+        </worldbody>
+        <sensor>
+          <contact name="cs" geom1="g" num="1" data="found"
+                   reduce="netforce"/>
+        </sensor>
+      </mujoco>"""
+    root = mjcf.from_xml_string(xml_string)
+    physics = mjcf.Physics.from_mjcf_model(root)
+    self.assertEqual(physics.model.nsensor, 1)
+    self.assertEqual(root.find('sensor', 'cs').geom1.name, 'g')
+
+  def test_jointinparent_is_scoped_on_attach(self):
+    child = mjcf.RootElement(model='child')
+    body = child.worldbody.add('body', name='b')
+    body.add('joint', name='j', type='hinge')
+    body.add('geom', name='g', size=[0.1])
+    child.actuator.add('general', name='a', jointinparent='j')
+    parent = mjcf.RootElement(model='parent')
+    parent.attach(child)
+    self.assertIn('jointinparent="child/j"', parent.to_xml_string())
+    physics = mjcf.Physics.from_mjcf_model(parent)
+    self.assertEqual(physics.model.nu, 1)
+
+  def test_custom_numeric_accepts_array_data(self):
+    root = mjcf.RootElement(model='m')
+    root.custom.add('numeric', name='x', data=[1, 2, 3])
+    physics = mjcf.Physics.from_mjcf_model(root)
+    self.assertEqual(physics.model.nnumericdata, 3)
+
+
 if __name__ == '__main__':
   absltest.main()