diff --git a/core/api/src/main/java/org/onlab/onos/net/intent/constraint/LatencyConstraint.java b/core/api/src/main/java/org/onlab/onos/net/intent/constraint/LatencyConstraint.java
index 45151ef..a2a25b6 100644
--- a/core/api/src/main/java/org/onlab/onos/net/intent/constraint/LatencyConstraint.java
+++ b/core/api/src/main/java/org/onlab/onos/net/intent/constraint/LatencyConstraint.java
@@ -42,6 +42,11 @@
         this.latency = latency;
     }
 
+    // Constructor for serialization
+    private LatencyConstraint() {
+        this.latency = Duration.ZERO;
+    }
+
     public Duration latency() {
         return latency;
     }