diff --git a/xml/schema/oscal_complete_schema.xsd b/xml/schema/oscal_complete_schema.xsd
index 0ed7f73115..41569c3f27 100644
--- a/xml/schema/oscal_complete_schema.xsd
+++ b/xml/schema/oscal_complete_schema.xsd
@@ -1847,7 +1847,7 @@
                   <xs:restriction base="xs:boolean"/>
                </xs:simpleType>
             </xs:element>
-            <xs:element name="custom" minOccurs="0" maxOccurs="1">
+            <xs:element name="custom" minOccurs="1" maxOccurs="1">
                <xs:complexType>
                   <xs:annotation>
                      <xs:appinfo>
diff --git a/xml/schema/oscal_profile_schema.xsd b/xml/schema/oscal_profile_schema.xsd
index e27d43d1e0..9337de97f1 100644
--- a/xml/schema/oscal_profile_schema.xsd
+++ b/xml/schema/oscal_profile_schema.xsd
@@ -154,7 +154,7 @@
                   <xs:restriction base="xs:boolean"/>
                </xs:simpleType>
             </xs:element>
-            <xs:element name="custom" minOccurs="0" maxOccurs="1">
+            <xs:element name="custom" minOccurs="1" maxOccurs="1">
                <xs:complexType>
                   <xs:annotation>
                      <xs:appinfo>