diff --git a/ecs_deploy/__init__.py b/ecs_deploy/__init__.py
index ad9237e..99b1e99 100644
--- a/ecs_deploy/__init__.py
+++ b/ecs_deploy/__init__.py
@@ -1 +1 @@
-VERSION = '1.11.2'
+VERSION = '1.11.3'
diff --git a/ecs_deploy/ecs.py b/ecs_deploy/ecs.py
index 29f8086..2b3f43b 100644
--- a/ecs_deploy/ecs.py
+++ b/ecs_deploy/ecs.py
@@ -221,7 +221,7 @@ class EcsTaskDefinition(object):
     def __init__(self, containerDefinitions, volumes, family, revision,
                  status, taskDefinitionArn, requiresAttributes=None,
                  taskRoleArn=None, executionRoleArn=None, compatibilities=None,
-                 tags=None, registeredAt=None, registeredBy=None, **kwargs):
+                 tags=None, registeredAt=None, deregisteredAt=None, registeredBy=None, **kwargs):
 
         self.containers = containerDefinitions
         self.volumes = volumes
@@ -241,6 +241,7 @@ def __init__(self, containerDefinitions, volumes, family, revision,
         # task definition. Just storing them for now.
         self.compatibilities = compatibilities
         self.registered_at = registeredAt
+        self.deregistered_at = deregisteredAt
         self.registered_by = registeredBy
 
     @property
diff --git a/tests/test_ecs.py b/tests/test_ecs.py
index 617780e..c4ecd04 100644
--- a/tests/test_ecs.py
+++ b/tests/test_ecs.py
@@ -70,6 +70,7 @@
     u'placementConstraints': {},
     u'registeredBy': 'foobar',
     u'registeredAt': '2021-01-20T14:33:44Z',
+    u'deregisteredAt': '2021-01-20T14:33:44Z',
     u'unknownProperty': u'lorem-ipsum',
     u'compatibilities': [u'EC2'],
 }