diff --git a/adapter-http.go b/adapter-http.go
index 131c8d4..927e03b 100644
--- a/adapter-http.go
+++ b/adapter-http.go
@@ -1,3 +1,18 @@
+/*
+	Copyright 2022 Dolysis Consulting Limited
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+		http://www.apache.org/licenses/LICENSE-2.0
+	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 License for the specific language governing permissions and
+	limitations under the License.
+
+	For changes see the git log
+*/
 package ipp
 
 import (
diff --git a/adapter-socket.go b/adapter-socket.go
index 75fd152..4c3b036 100644
--- a/adapter-socket.go
+++ b/adapter-socket.go
@@ -1,3 +1,18 @@
+/*
+	Copyright 2022 Dolysis Consulting Limited
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+		http://www.apache.org/licenses/LICENSE-2.0
+	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 License for the specific language governing permissions and
+	limitations under the License.
+
+	For changes see the git log
+*/
 package ipp
 
 import (
diff --git a/adapter.go b/adapter.go
index 15ad2d0..881a263 100644
--- a/adapter.go
+++ b/adapter.go
@@ -1,3 +1,18 @@
+/*
+	Copyright 2022 Dolysis Consulting Limited
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+		http://www.apache.org/licenses/LICENSE-2.0
+	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 License for the specific language governing permissions and
+	limitations under the License.
+
+	For changes see the git log
+*/
 package ipp
 
 import "io"
diff --git a/attribute.go b/attribute.go
index 412a430..1496539 100644
--- a/attribute.go
+++ b/attribute.go
@@ -1,3 +1,18 @@
+/*
+	Copyright 2022 Dolysis Consulting Limited
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+		http://www.apache.org/licenses/LICENSE-2.0
+	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 License for the specific language governing permissions and
+	limitations under the License.
+
+	For changes see the git log
+*/
 package ipp
 
 import (
diff --git a/attribute_test.go b/attribute_test.go
index 9793638..48a5d9f 100644
--- a/attribute_test.go
+++ b/attribute_test.go
@@ -1,3 +1,18 @@
+/*
+	Copyright 2022 Dolysis Consulting Limited
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+		http://www.apache.org/licenses/LICENSE-2.0
+	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 License for the specific language governing permissions and
+	limitations under the License.
+
+	For changes see the git log
+*/
 package ipp
 
 import (
diff --git a/constants.go b/constants.go
index e6e1a02..c358f15 100644
--- a/constants.go
+++ b/constants.go
@@ -1,3 +1,18 @@
+/*
+	Copyright 2022 Dolysis Consulting Limited
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+		http://www.apache.org/licenses/LICENSE-2.0
+	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 License for the specific language governing permissions and
+	limitations under the License.
+
+	For changes see the git log
+*/
 package ipp
 
 // ipp status codes
diff --git a/cups-client.go b/cups-client.go
index 54c4589..e4f208c 100644
--- a/cups-client.go
+++ b/cups-client.go
@@ -1,3 +1,18 @@
+/*
+	Copyright 2022 Dolysis Consulting Limited
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+		http://www.apache.org/licenses/LICENSE-2.0
+	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 License for the specific language governing permissions and
+	limitations under the License.
+
+	For changes see the git log
+*/
 package ipp
 
 import (
diff --git a/error.go b/error.go
index e4edf5e..9221abb 100644
--- a/error.go
+++ b/error.go
@@ -1,3 +1,18 @@
+/*
+	Copyright 2022 Dolysis Consulting Limited
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+		http://www.apache.org/licenses/LICENSE-2.0
+	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 License for the specific language governing permissions and
+	limitations under the License.
+
+	For changes see the git log
+*/
 package ipp
 
 import "fmt"
diff --git a/ipp-client.go b/ipp-client.go
index 1451746..b0d25cc 100644
--- a/ipp-client.go
+++ b/ipp-client.go
@@ -1,3 +1,18 @@
+/*
+	Copyright 2022 Dolysis Consulting Limited
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+		http://www.apache.org/licenses/LICENSE-2.0
+	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 License for the specific language governing permissions and
+	limitations under the License.
+
+	For changes see the git log
+*/
 package ipp
 
 import (
diff --git a/request.go b/request.go
index f0244a7..3c0e516 100644
--- a/request.go
+++ b/request.go
@@ -1,3 +1,18 @@
+/*
+	Copyright 2022 Dolysis Consulting Limited
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+		http://www.apache.org/licenses/LICENSE-2.0
+	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 License for the specific language governing permissions and
+	limitations under the License.
+
+	For changes see the git log
+*/
 package ipp
 
 import (
diff --git a/response.go b/response.go
index 0ba4ed9..e775b59 100644
--- a/response.go
+++ b/response.go
@@ -1,3 +1,18 @@
+/*
+	Copyright 2022 Dolysis Consulting Limited
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+		http://www.apache.org/licenses/LICENSE-2.0
+	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 License for the specific language governing permissions and
+	limitations under the License.
+
+	For changes see the git log
+*/
 package ipp
 
 import (
diff --git a/utils.go b/utils.go
index 62689a3..b2fa873 100644
--- a/utils.go
+++ b/utils.go
@@ -1,3 +1,18 @@
+/*
+	Copyright 2022 Dolysis Consulting Limited
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+		http://www.apache.org/licenses/LICENSE-2.0
+	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 License for the specific language governing permissions and
+	limitations under the License.
+
+	For changes see the git log
+*/
 package ipp
 
 import (