diff --git a/src/Command/UpdateLicensesCommand.php b/src/Command/UpdateLicensesCommand.php
index 31b9d75..e30413a 100644
--- a/src/Command/UpdateLicensesCommand.php
+++ b/src/Command/UpdateLicensesCommand.php
@@ -22,6 +22,7 @@
 
 namespace PrestaShop\HeaderStamp\Command;
 
+use Exception;
 use PhpParser\Node\Stmt;
 use PhpParser\ParserFactory;
 use PrestaShop\HeaderStamp\LicenseHeader;
@@ -399,32 +400,50 @@ private function addLicenseToHtmlFile(SplFileInfo $file): void
         $this->addLicenseToFile($file, '<!--', '-->');
     }
 
-    private function addLicenseToJsonFile(SplFileInfo $file): bool
+    /**
+     * @throws Exception
+     */
+    private function addLicenseToJsonFile(SplFileInfo $file): void
     {
         if (!in_array($file->getFilename(), ['composer.json', 'package.json'])) {
-            return false;
+            return;
         }
 
         $content = json_decode($file->getContents(), true);
-        $oldContent = $content;
-        $content['author'] = 'PrestaShop';
+
+        $authorDetails = [
+            'name' => 'PrestaShop SA',
+            'email' => 'contact@prestashop.com',
+        ];
+
+        // update author information depending of file
+        if ('composer.json' === $file->getFilename()) {
+            $content['authors'] = [$authorDetails];
+        } else { // package.json
+            $content['author'] = $authorDetails;
+        }
+
         $content['license'] = (false !== strpos($this->license, 'afl')) ? 'AFL-3.0' : 'OSL-3.0';
 
+        $encodedContent = json_encode($content, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT);
+
+        if (!$encodedContent) {
+            throw new Exception('File can not be encoded to JSON format');
+        }
+
+        // add blank line in end of file if not exist
+        if (substr($encodedContent, -1) !== "\n") {
+            $encodedContent .= "\n";
+        }
+
         if (!$this->runAsDry) {
-            $result = file_put_contents(
+            file_put_contents(
                 $this->targetDirectory . '/' . $file->getRelativePathname(),
-                json_encode($content, JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT)
+                $encodedContent
             );
-        } else {
-            $result = true;
         }
 
-        $newFileContent = (string) json_encode($content);
-        $oldFileContent = (string) json_encode($oldContent);
-
-        $this->reportOperationResult($newFileContent, $oldFileContent, $file->getFilename());
-
-        return false !== $result;
+        $this->reportOperationResult($encodedContent, $file->getContents(), $file->getFilename());
     }
 
     /**
diff --git a/tests/integration/expected/dashproducts/composer.json b/tests/integration/expected/dashproducts/composer.json
index 8b76f6a..3bf140b 100644
--- a/tests/integration/expected/dashproducts/composer.json
+++ b/tests/integration/expected/dashproducts/composer.json
@@ -15,6 +15,5 @@
     "config": {
         "preferred-install": "dist"
     },
-    "type": "prestashop-module",
-    "author": "PrestaShop"
-}
\ No newline at end of file
+    "type": "prestashop-module"
+}
diff --git a/tests/integration/expected/gsitemap/composer.json b/tests/integration/expected/gsitemap/composer.json
index c3dfa4b..9e7c304 100644
--- a/tests/integration/expected/gsitemap/composer.json
+++ b/tests/integration/expected/gsitemap/composer.json
@@ -3,12 +3,6 @@
     "description": "PrestaShop module gsitemap",
     "homepage": "https://github.com/PrestaShop/gsitemap",
     "license": "AFL-3.0",
-    "authors": [
-        {
-            "name": "PrestaShop SA",
-            "email": "contact@prestashop.com"
-        }
-    ],
     "require": {
         "php": ">=5.6.0"
     },
@@ -16,5 +10,10 @@
         "preferred-install": "dist"
     },
     "type": "prestashop-module",
-    "author": "PrestaShop"
-}
\ No newline at end of file
+    "authors": [
+        {
+            "name": "PrestaShop SA",
+            "email": "contact@prestashop.com"
+        }
+    ]
+}
diff --git a/tests/integration/module-samples/dashproducts/composer.json b/tests/integration/module-samples/dashproducts/composer.json
index 8b76f6a..3bf140b 100644
--- a/tests/integration/module-samples/dashproducts/composer.json
+++ b/tests/integration/module-samples/dashproducts/composer.json
@@ -15,6 +15,5 @@
     "config": {
         "preferred-install": "dist"
     },
-    "type": "prestashop-module",
-    "author": "PrestaShop"
-}
\ No newline at end of file
+    "type": "prestashop-module"
+}
diff --git a/tests/integration/module-samples/gsitemap/composer.json b/tests/integration/module-samples/gsitemap/composer.json
index c3dfa4b..7ecd64c 100644
--- a/tests/integration/module-samples/gsitemap/composer.json
+++ b/tests/integration/module-samples/gsitemap/composer.json
@@ -3,18 +3,11 @@
     "description": "PrestaShop module gsitemap",
     "homepage": "https://github.com/PrestaShop/gsitemap",
     "license": "AFL-3.0",
-    "authors": [
-        {
-            "name": "PrestaShop SA",
-            "email": "contact@prestashop.com"
-        }
-    ],
     "require": {
         "php": ">=5.6.0"
     },
     "config": {
         "preferred-install": "dist"
     },
-    "type": "prestashop-module",
-    "author": "PrestaShop"
-}
\ No newline at end of file
+    "type": "prestashop-module"
+}
diff --git a/tests/integration/runner/FolderComparator.php b/tests/integration/runner/FolderComparator.php
index 0c4af14..579badc 100644
--- a/tests/integration/runner/FolderComparator.php
+++ b/tests/integration/runner/FolderComparator.php
@@ -32,7 +32,6 @@ class FolderComparator
         'autoload_static.php',
         'autoload_real.php',
         'ClassLoader.php',
-        'composer.json',
     ];
 
     /**