diff --git a/MQTTClient-C/src/CMakeLists.txt b/MQTTClient-C/src/CMakeLists.txt
index ecd9b0b..331196a 100644
--- a/MQTTClient-C/src/CMakeLists.txt
+++ b/MQTTClient-C/src/CMakeLists.txt
@@ -1,5 +1,5 @@
 #*******************************************************************************
-#  Copyright (c) 2017 IBM Corp.
+#  Copyright (c) 2017, 2023 IBM Corp.
 #
 #  All rights reserved. This program and the accompanying materials
 #  are made available under the terms of the Eclipse Public License v1.0
diff --git a/MQTTPacket/src/MQTTPacketCommon.h b/MQTTPacket/src/MQTTPacketCommon.h
index b3f687e..1eb7ee8 100644
--- a/MQTTPacket/src/MQTTPacketCommon.h
+++ b/MQTTPacket/src/MQTTPacketCommon.h
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2014, 2023 IBM Corp., Ian Craggs and others
+ * Copyright (c) 2023 Microsoft Corporation. All rights reserved.
  *
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
@@ -10,9 +10,6 @@
  * and the Eclipse Distribution License is available at
  *   http://www.eclipse.org/org/documents/edl-v10.php.
  *
- * Contributors:
- *    Ian Craggs - initial API and implementation and/or initial documentation
- *    Xiang Rong - 442039 Add makefile to Embedded C client
  *******************************************************************************/
 
 #ifndef MQTTPACKETCOMMON_H_
diff --git a/MQTTPacket/src/V3/MQTTSubscribe.h b/MQTTPacket/src/V3/MQTTSubscribe.h
index 18f53cf..ae0e4a0 100644
--- a/MQTTPacket/src/V3/MQTTSubscribe.h
+++ b/MQTTPacket/src/V3/MQTTSubscribe.h
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2014 IBM Corp.
+ * Copyright (c) 2014, 2023 IBM Corp.
  *
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
diff --git a/MQTTPacket/src/V5/MQTTV5Format.c b/MQTTPacket/src/V5/MQTTV5Format.c
index 6b1bcc4..447fe62 100644
--- a/MQTTPacket/src/V5/MQTTV5Format.c
+++ b/MQTTPacket/src/V5/MQTTV5Format.c
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2014, 2023 IBM Corp.
+ * Copyright (c) 2023 Microsoft Corporation. All rights reserved.
  *
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
@@ -10,8 +10,6 @@
  * and the Eclipse Distribution License is available at
  *   http://www.eclipse.org/org/documents/edl-v10.php.
  *
- * Contributors:
- *    Ian Craggs - initial API and implementation and/or initial documentation
  *******************************************************************************/
 
 // TODO: Add MQTTv5 properties implementation (some of the code exists in v5log.h), application must provide memory.
diff --git a/MQTTPacket/src/V5/MQTTV5Format.h b/MQTTPacket/src/V5/MQTTV5Format.h
index bbccbeb..5179773 100644
--- a/MQTTPacket/src/V5/MQTTV5Format.h
+++ b/MQTTPacket/src/V5/MQTTV5Format.h
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2014, 2023 IBM Corp., Ian Craggs and others
+ * Copyright (c) 2023 Microsoft Corporation. All rights reserved.
  *
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
@@ -10,8 +10,6 @@
  * and the Eclipse Distribution License is available at
  *   http://www.eclipse.org/org/documents/edl-v10.php.
  *
- * Contributors:
- *    Ian Craggs - initial API and implementation and/or initial documentation
  *******************************************************************************/
 
 #if !defined(MQTTV5FORMAT_H)