diff --git a/.copywrite.hcl b/.copywrite.hcl
new file mode 100644
index 0000000..ada7d74
--- /dev/null
+++ b/.copywrite.hcl
@@ -0,0 +1,13 @@
+schema_version = 1
+
+project {
+  license        = "MPL-2.0"
+  copyright_year = 2019
+
+  # (OPTIONAL) A list of globs that should not have copyright/license headers.
+  # Supports doublestar glob patterns for more flexibility in defining which
+  # files or folders should be ignored
+  header_ignore = [
+    "testdata/**",
+  ]
+}
diff --git a/action.go b/action.go
index 51c4c83..c74f7e6 100644
--- a/action.go
+++ b/action.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 // Action is a valid action type for a resource change.
diff --git a/cmd/round-trip-dumper/main.go b/cmd/round-trip-dumper/main.go
index b07e404..92c2270 100644
--- a/cmd/round-trip-dumper/main.go
+++ b/cmd/round-trip-dumper/main.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package main
 
 import (
diff --git a/config.go b/config.go
index 5ebe4bc..e8ea638 100644
--- a/config.go
+++ b/config.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/config_test.go b/config_test.go
index 1cd17fa..c0cf1e0 100644
--- a/config_test.go
+++ b/config_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/expression.go b/expression.go
index 8a39fac..5ecb15c 100644
--- a/expression.go
+++ b/expression.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import "encoding/json"
diff --git a/expression_test.go b/expression_test.go
index aea1eea..1fb74ef 100644
--- a/expression_test.go
+++ b/expression_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/metadata.go b/metadata.go
index 70d7ce4..eb52577 100644
--- a/metadata.go
+++ b/metadata.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/metadata_test.go b/metadata_test.go
index 1bc0072..9938a09 100644
--- a/metadata_test.go
+++ b/metadata_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/parse_test.go b/parse_test.go
index 78495ef..79c9a66 100644
--- a/parse_test.go
+++ b/parse_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/plan.go b/plan.go
index 6cfd533..cbbf186 100644
--- a/plan.go
+++ b/plan.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/plan_test.go b/plan_test.go
index 003e966..c74826d 100644
--- a/plan_test.go
+++ b/plan_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/sanitize/copy.go b/sanitize/copy.go
index 27991fd..01913a1 100644
--- a/sanitize/copy.go
+++ b/sanitize/copy.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package sanitize
 
 import (
diff --git a/sanitize/copy_test.go b/sanitize/copy_test.go
index 63bff6c..be7d6a4 100644
--- a/sanitize/copy_test.go
+++ b/sanitize/copy_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package sanitize
 
 import (
diff --git a/sanitize/sanitize_change.go b/sanitize/sanitize_change.go
index 3396438..086cca1 100644
--- a/sanitize/sanitize_change.go
+++ b/sanitize/sanitize_change.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package sanitize
 
 import (
diff --git a/sanitize/sanitize_change_test.go b/sanitize/sanitize_change_test.go
index 775a1f4..0741b2a 100644
--- a/sanitize/sanitize_change_test.go
+++ b/sanitize/sanitize_change_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package sanitize
 
 import (
diff --git a/sanitize/sanitize_plan.go b/sanitize/sanitize_plan.go
index 6d009f0..d03b8fa 100644
--- a/sanitize/sanitize_plan.go
+++ b/sanitize/sanitize_plan.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package sanitize
 
 import (
diff --git a/sanitize/sanitize_plan_test.go b/sanitize/sanitize_plan_test.go
index 18ad5c3..9506423 100644
--- a/sanitize/sanitize_plan_test.go
+++ b/sanitize/sanitize_plan_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package sanitize
 
 import (
diff --git a/sanitize/sanitize_plan_variables.go b/sanitize/sanitize_plan_variables.go
index 7d86a12..b800ebb 100644
--- a/sanitize/sanitize_plan_variables.go
+++ b/sanitize/sanitize_plan_variables.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package sanitize
 
 import (
diff --git a/sanitize/sanitize_plan_variables_test.go b/sanitize/sanitize_plan_variables_test.go
index 19164ce..482b181 100644
--- a/sanitize/sanitize_plan_variables_test.go
+++ b/sanitize/sanitize_plan_variables_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package sanitize
 
 import (
diff --git a/sanitize/sanitize_state.go b/sanitize/sanitize_state.go
index 3aba29b..e1fe1a7 100644
--- a/sanitize/sanitize_state.go
+++ b/sanitize/sanitize_state.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package sanitize
 
 import (
diff --git a/sanitize/sanitize_state_test.go b/sanitize/sanitize_state_test.go
index 7ca194a..ac7d501 100644
--- a/sanitize/sanitize_state_test.go
+++ b/sanitize/sanitize_state_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package sanitize
 
 import (
diff --git a/schemas.go b/schemas.go
index f7c8abd..64f87d8 100644
--- a/schemas.go
+++ b/schemas.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/schemas_test.go b/schemas_test.go
index a02ffba..5044559 100644
--- a/schemas_test.go
+++ b/schemas_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/state.go b/state.go
index 3c3f6a4..02f0dc6 100644
--- a/state.go
+++ b/state.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/state_test.go b/state_test.go
index c1b9fa4..dee9021 100644
--- a/state_test.go
+++ b/state_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/tfjson.go b/tfjson.go
index 55f9ac4..3a78a4f 100644
--- a/tfjson.go
+++ b/tfjson.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 // Package tfjson is a de-coupled helper library containing types for
 // the plan format output by "terraform show -json" command. This
 // command is designed for the export of Terraform plan data in
diff --git a/validate.go b/validate.go
index 97b82d0..53652ef 100644
--- a/validate.go
+++ b/validate.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/validate_test.go b/validate_test.go
index c876045..6b7860f 100644
--- a/validate_test.go
+++ b/validate_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (
diff --git a/version.go b/version.go
index 16f0a85..7516ad6 100644
--- a/version.go
+++ b/version.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 // VersionOutput represents output from the version -json command
diff --git a/version_test.go b/version_test.go
index dcd7317..b935fbd 100644
--- a/version_test.go
+++ b/version_test.go
@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 package tfjson
 
 import (