diff --git a/src/main/cljc/org/domaindrivenarchitecture/activity_pub_poc/activitystreams2.cljc b/src/main/cljc/org/domaindrivenarchitecture/activity_pub_poc/activitystreams2.cljc
index b90e766..b5a25d5 100644
--- a/src/main/cljc/org/domaindrivenarchitecture/activity_pub_poc/activitystreams2.cljc
+++ b/src/main/cljc/org/domaindrivenarchitecture/activity_pub_poc/activitystreams2.cljc
@@ -14,7 +14,7 @@
 (s/def ::Object
   (s/and
    ::owl/Class
-   (sh/map-spec (s/keys :opt-un [::id ::type ::attachment ::bcc ::bto]))))
+   (sh/map-spec (s/keys :opt-un [::id ::type ::attachment ::bcc ::bto ::cc ::to]))))
 
 ;http://www.w3.org/ns/activitystreams#Link
 ;TODO: definition in progress
@@ -73,6 +73,18 @@
          ::Object
          ::Link))
 
+;http://www.w3.org/ns/activitystreams#cc
+(s/def ::cc
+  (s/and ::owl/ObjectProperty
+         ::Object
+         ::Link))
+
+;http://www.w3.org/ns/activitystreams#to
+(s/def ::to
+  (s/and ::owl/ObjectProperty
+         ::Object
+         ::Link))
+
 ;https://www.w3.org/TR/activitystreams-vocabulary/#dfn-type
 ;TODO: this can not be found in the ttl / namespace. Where is this exactly defined?
 (s/def ::type
diff --git a/src/test/cljc/org/domaindrivenarchitecture/activity_pub_poc/activitystreams2_test.cljc b/src/test/cljc/org/domaindrivenarchitecture/activity_pub_poc/activitystreams2_test.cljc
index 22c7596..f9ce1fe 100644
--- a/src/test/cljc/org/domaindrivenarchitecture/activity_pub_poc/activitystreams2_test.cljc
+++ b/src/test/cljc/org/domaindrivenarchitecture/activity_pub_poc/activitystreams2_test.cljc
@@ -51,6 +51,12 @@
 (deftest bto-test
   (is (s/valid? ::sut/bto ["http://joe.example.org"])))
 
+(deftest cc-test
+  (is (s/valid? ::sut/cc ["http://joe.example.org"])))
+
+(deftest to-test
+  (is (s/valid? ::sut/to ["http://joe.example.org"])))
+
 (deftest Activity-test
   (is (s/valid? ::sut/Activity
                 {:type "Activity",