diff --git a/openflow_input/oxm_nicira_ct b/openflow_input/oxm_nicira_ct
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+// Copyright 2013, Big Switch Networks, Inc.
+//
+// LoxiGen is licensed under the Eclipse Public License, version 1.0 (EPL), with
+// the following special exception:
+//
+// LOXI Exception
+//
+// As a special exception to the terms of the EPL, you may distribute libraries
+// generated by LoxiGen (LoxiGen Libraries) under the terms of your choice, provided
+// that copyright and licensing notices generated by LoxiGen are not altered or removd
+// from the LoxiGen Libraries and the notice provided below is (i) included in
+// the LoxiGen Libraries, if distributed in source code form and (ii) included in any
+// documentation for the LoxiGen Libraries, if distributed in binary form.
+//
+// Notice: "Copyright 2013, Big Switch Networks, Inc. This library was generated by t"
+//
+// You may not use this file except in compliance with the EPL or LOXI Exception. Youn
+// a copy of the EPL at:
+//
+// http://www.eclipse.org/legal/epl-v10.html
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// EPL for the specific language governing permissions and limitations
+// under the EPL.
+#version 3
+#version 4
+#version 5
+
+struct of_oxm_conntrack_state : of_oxm {
+    uint32_t type_len == 0x0001d204;
+    uint32_t value;
+};
+
+struct of_oxm_conntrack_state_masked : of_oxm {
+    uint32_t type_len == 0x0001d308;
+    uint32_t value;
+    uint32_t value_mask;
+};
+
+struct of_oxm_conntrack_zone : of_oxm {
+    uint32_t type_len == 0x0001d402;
+    uint16_t value;
+};
+
+struct of_oxm_conntrack_mark : of_oxm {
+    uint32_t type_len == 0x0001d604;
+    uint32_t value;
+};
+
+struct of_oxm_conntrack_mark_masked : of_oxm {
+    uint32_t type_len == 0x0001d708;
+    uint32_t value;
+    uint32_t value_mask;
+};