diff --git a/src/DigitalData.DEX.Domain/Entities/Entity.cs b/src/DigitalData.DEX.Domain/Entities/Entity.cs
new file mode 100644
index 0000000..262c836
--- /dev/null
+++ b/src/DigitalData.DEX.Domain/Entities/Entity.cs
@@ -0,0 +1,5 @@
+namespace DigitalData.DEX.Domain.Entities;
+
+public abstract class Entity
+{
+}
diff --git a/src/DigitalData.DEX.Domain/Entities/Output.cs b/src/DigitalData.DEX.Domain/Entities/Output.cs
index 7451268..29fa0a8 100644
--- a/src/DigitalData.DEX.Domain/Entities/Output.cs
+++ b/src/DigitalData.DEX.Domain/Entities/Output.cs
@@ -3,6 +3,6 @@
 namespace DigitalData.DEX.Domain.Entities;
 
 [Table("TBDEX_OUTPUT", Schema = "dbo")]
-public class Output
+public class Output : Entity
 {
 }
diff --git a/src/DigitalData.DEX.Domain/Entities/OutputReferences.cs b/src/DigitalData.DEX.Domain/Entities/OutputReferences.cs
index 8efe2f5..76d9d8b 100644
--- a/src/DigitalData.DEX.Domain/Entities/OutputReferences.cs
+++ b/src/DigitalData.DEX.Domain/Entities/OutputReferences.cs
@@ -3,6 +3,6 @@
 namespace DigitalData.DEX.Domain.Entities;
 
 [Table("TBDEX_OUTPUT_REFERENCES", Schema = "dbo")]
-public class OutputReferences
+public class OutputReferences : Entity
 {
 }