diff --git a/includes/Checker/Checks/Plugin_Repo/Plugin_Readme_Check.php b/includes/Checker/Checks/Plugin_Repo/Plugin_Readme_Check.php
index 8e9ea089..71ee0e53 100644
--- a/includes/Checker/Checks/Plugin_Repo/Plugin_Readme_Check.php
+++ b/includes/Checker/Checks/Plugin_Repo/Plugin_Readme_Check.php
@@ -354,7 +354,7 @@ private function check_license( Check_Result $result, string $readme_file, Parse
 		}
 
 		// Checks for a valid license in Plugin Header.
-		if ( ! empty( $plugin_license ) && ! preg_match( '/GPL|GNU|MIT|FreeBSD|New BSD|BSD-3-Clause|BSD 3 Clause|OpenLDAP|Expat|Apache/im', $plugin_license ) ) {
+		if ( ! empty( $plugin_license ) && ! preg_match( '/GPL|GNU|MIT|FreeBSD|New BSD|BSD-3-Clause|BSD 3 Clause|OpenLDAP|Expat|Apache|MPL20/im', $plugin_license ) ) {
 			$this->add_result_error_for_file(
 				$result,
 				__( '<strong>Your plugin has an invalid license declared in Plugin Header.</strong><br>Please update your readme with a valid GPL license identifier. It is necessary to declare the license of this plugin. You can do this by using the fields available both in the plugin readme and in the plugin headers.', 'plugin-check' ),
diff --git a/tests/phpunit/testdata/plugins/test-plugin-plugin-readme-mpl1-license-with-errors/load.php b/tests/phpunit/testdata/plugins/test-plugin-plugin-readme-mpl1-license-with-errors/load.php
new file mode 100644
index 00000000..34a6c3c6
--- /dev/null
+++ b/tests/phpunit/testdata/plugins/test-plugin-plugin-readme-mpl1-license-with-errors/load.php
@@ -0,0 +1,16 @@
+<?php
+/**
+ * Plugin Name: Test Plugin MPL-1.0 (license) with errors
+ * Plugin URI: https://github.com/WordPress/plugin-check
+ * Description: Test plugin for the Readme check.
+ * Requires at least: 6.0
+ * Requires PHP: 5.6
+ * Version: 1.0.0
+ * Author: WordPress Performance Team
+ * Author URI: https://make.wordpress.org/performance/
+ * License: MPL-1.0
+ * License URI: https://www.mozilla.org/en-US/MPL/2.0/FAQ/
+ * Text Domain: test-plugin-plugin-readme-mpl1-license-with-errors
+ *
+ * @package test-plugin-plugin-readme-mpl1-license-with-errors
+ */
diff --git a/tests/phpunit/testdata/plugins/test-plugin-plugin-readme-mpl1-license-with-errors/readme.txt b/tests/phpunit/testdata/plugins/test-plugin-plugin-readme-mpl1-license-with-errors/readme.txt
new file mode 100644
index 00000000..7e712799
--- /dev/null
+++ b/tests/phpunit/testdata/plugins/test-plugin-plugin-readme-mpl1-license-with-errors/readme.txt
@@ -0,0 +1,13 @@
+
+=== Test Plugin with readme and MPL 1.0 license ===
+
+Contributors:      plugin-check
+Requires at least: 6.0
+Tested up to:      6.7
+Requires PHP:      5.6
+Stable tag:        1.0.0
+License:           MPL-1.0
+License URI:       https://www.mozilla.org/en-US/MPL/1.0/FAQ/
+Tags:              testing, security
+
+Plugin description.
diff --git a/tests/phpunit/testdata/plugins/test-plugin-plugin-readme-mpl2-license-without-errors/load.php b/tests/phpunit/testdata/plugins/test-plugin-plugin-readme-mpl2-license-without-errors/load.php
new file mode 100644
index 00000000..d92bdcb5
--- /dev/null
+++ b/tests/phpunit/testdata/plugins/test-plugin-plugin-readme-mpl2-license-without-errors/load.php
@@ -0,0 +1,16 @@
+<?php
+/**
+ * Plugin Name: Test Plugin MPL-2.0 (license) without errors
+ * Plugin URI: https://github.com/WordPress/plugin-check
+ * Description: Test plugin for the Readme check.
+ * Requires at least: 6.0
+ * Requires PHP: 5.6
+ * Version: 1.0.0
+ * Author: WordPress Performance Team
+ * Author URI: https://make.wordpress.org/performance/
+ * License: MPL-2.0
+ * License URI: https://www.mozilla.org/en-US/MPL/2.0/FAQ/
+ * Text Domain: test-plugin-plugin-readme-mpl2-license-without-errors
+ *
+ * @package test-plugin-plugin-readme-mpl2-license-without-errors
+ */
diff --git a/tests/phpunit/testdata/plugins/test-plugin-plugin-readme-mpl2-license-without-errors/readme.txt b/tests/phpunit/testdata/plugins/test-plugin-plugin-readme-mpl2-license-without-errors/readme.txt
new file mode 100644
index 00000000..ed3c5894
--- /dev/null
+++ b/tests/phpunit/testdata/plugins/test-plugin-plugin-readme-mpl2-license-without-errors/readme.txt
@@ -0,0 +1,13 @@
+
+=== Test Plugin with readme and MPL 2.0 license ===
+
+Contributors:      plugin-check
+Requires at least: 6.0
+Tested up to:      6.7
+Requires PHP:      5.6
+Stable tag:        1.0.0
+License:           MPL-2.0
+License URI:       https://www.mozilla.org/en-US/MPL/2.0/FAQ/
+Tags:              testing, security
+
+Plugin description.
diff --git a/tests/phpunit/tests/Checker/Checks/Plugin_Readme_Check_Tests.php b/tests/phpunit/tests/Checker/Checks/Plugin_Readme_Check_Tests.php
index d2f9cddb..6bbb60c6 100644
--- a/tests/phpunit/tests/Checker/Checks/Plugin_Readme_Check_Tests.php
+++ b/tests/phpunit/tests/Checker/Checks/Plugin_Readme_Check_Tests.php
@@ -180,6 +180,36 @@ public function test_run_with_errors_no_license() {
 		$this->assertCount( 1, wp_list_filter( $errors['readme.txt'][0][0], array( 'code' => 'no_license' ) ) );
 	}
 
+	public function test_run_without_error_mpl2_license() {
+		$readme_check  = new Plugin_Readme_Check();
+		$check_context = new Check_Context( UNIT_TESTS_PLUGIN_DIR . 'test-plugin-plugin-readme-mpl2-license-without-errors/load.php' );
+		$check_result  = new Check_Result( $check_context );
+
+		$readme_check->run( $check_result );
+
+		$errors = $check_result->get_errors();
+
+		$this->assertEmpty( $errors );
+	}
+
+	public function test_run_with_errors_mpl1_license() {
+		$readme_check  = new Plugin_Readme_Check();
+		$check_context = new Check_Context( UNIT_TESTS_PLUGIN_DIR . 'test-plugin-plugin-readme-mpl1-license-with-errors/load.php' );
+		$check_result  = new Check_Result( $check_context );
+
+		$readme_check->run( $check_result );
+
+		$errors = $check_result->get_errors();
+
+		$this->assertNotEmpty( $errors );
+		$this->assertArrayHasKey( 'load.php', $errors );
+
+		// Check for invalid license.
+		$this->assertArrayHasKey( 0, $errors['load.php'] );
+		$this->assertArrayHasKey( 0, $errors['load.php'][0] );
+		$this->assertCount( 1, wp_list_filter( $errors['load.php'][0][0], array( 'code' => 'invalid_license' ) ) );
+	}
+
 	public function test_run_with_errors_tested_upto() {
 		$readme_check  = new Plugin_Readme_Check();
 		$check_context = new Check_Context( UNIT_TESTS_PLUGIN_DIR . 'test-plugin-plugin-readme-errors-tested-upto/load.php' );