diff --git a/tests/patched.py b/tests/patched.py
index 4fcc2c7d2d76cd9ec7107ff357bdd3d0cea24965..7c0eff471dfe1643f6f6391177021620226da694 100644
--- a/tests/patched.py
+++ b/tests/patched.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2016-2020 Maël Azimi <m.a@moul.re>
+
+Silkaj is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+Silkaj is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with Silkaj. If not, see <https://www.gnu.org/licenses/>.
+"""
+
 # This file contains patched functions for testing purposes.
 
 from silkaj.constants import G1_SYMBOL
diff --git a/tests/test_end_to_end.py b/tests/test_end_to_end.py
index 563a8a39c817dab04a25a43e47646a2e093995b0..e761c2d1437a77aefd9f8ceabbd4156e3a672e54 100644
--- a/tests/test_end_to_end.py
+++ b/tests/test_end_to_end.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2016-2020 Maël Azimi <m.a@moul.re>
+
+Silkaj is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+Silkaj is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with Silkaj. If not, see <https://www.gnu.org/licenses/>.
+"""
+
 from subprocess import check_output
 
 silkaj = ["poetry", "run", "silkaj"]
diff --git a/tests/test_tx.py b/tests/test_tx.py
index 6a6a95180a9797542606c4a6516714b84d897c75..4ac609cda0756de4e51761fb833d92e81d6258f4 100644
--- a/tests/test_tx.py
+++ b/tests/test_tx.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2016-2020 Maël Azimi <m.a@moul.re>
+
+Silkaj is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+Silkaj is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with Silkaj. If not, see <https://www.gnu.org/licenses/>.
+"""
+
 import pytest
 from click.testing import CliRunner
 from silkaj.tx import transaction_amount
diff --git a/tests/test_tx_history.py b/tests/test_tx_history.py
index feae06b7b208197ee446fb25621b4fd09d61e55b..60111fbc9ee9a591070620c2f34b7b3b6798dac8 100644
--- a/tests/test_tx_history.py
+++ b/tests/test_tx_history.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2016-2020 Maël Azimi <m.a@moul.re>
+
+Silkaj is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+Silkaj is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with Silkaj. If not, see <https://www.gnu.org/licenses/>.
+"""
+
 import pytest
 from duniterpy.api.client import Client
 from silkaj.tx_history import (
diff --git a/tests/test_unit_cert.py b/tests/test_unit_cert.py
index da7d7f6f041bf17dd0be2af92b682c6a4227e845..9f7092e06140f1671a17e25d461d0d4da0104e5b 100644
--- a/tests/test_unit_cert.py
+++ b/tests/test_unit_cert.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2016-2020 Maël Azimi <m.a@moul.re>
+
+Silkaj is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+Silkaj is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with Silkaj. If not, see <https://www.gnu.org/licenses/>.
+"""
+
 from unittest.mock import patch
 
 from silkaj.cert import certification_confirmation
diff --git a/tests/test_unit_tx.py b/tests/test_unit_tx.py
index 1a6f352f9558e7f9653d1e81787c08e063d5d2e5..11df8bf8f5dcf9128aa7e0b166f880a9694728d4 100644
--- a/tests/test_unit_tx.py
+++ b/tests/test_unit_tx.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2016-2020 Maël Azimi <m.a@moul.re>
+
+Silkaj is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+Silkaj is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with Silkaj. If not, see <https://www.gnu.org/licenses/>.
+"""
+
 import pytest
 from silkaj.tx import (
     truncBase,