diff --git a/admin/tool/messageinbound/classes/manager.php b/admin/tool/messageinbound/classes/manager.php
index 74de88ac136..16f7d19f67f 100644
--- a/admin/tool/messageinbound/classes/manager.php
+++ b/admin/tool/messageinbound/classes/manager.php
@@ -310,6 +310,16 @@ class manager {
         return true;
     }
 
+    /**
+     * Remove older verification failures.
+     *
+     * @return void
+     */
+    public function tidy_old_verification_failures() {
+        global $DB;
+        $DB->delete_records_select('messageinbound_messagelist', 'timecreated < :time', ['time' => time() - DAYSECS]);
+    }
+
     /**
      * Process a message and pass it through the Inbound Message handling systems.
      *
diff --git a/admin/tool/messageinbound/classes/privacy/provider.php b/admin/tool/messageinbound/classes/privacy/provider.php
new file mode 100644
index 00000000000..de6fc9a0144
--- /dev/null
+++ b/admin/tool/messageinbound/classes/privacy/provider.php
@@ -0,0 +1,173 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Data provider.
+ *
+ * @package    tool_messageinbound
+ * @copyright  2018 Frédéric Massart
+ * @author     Frédéric Massart <fred@branchup.tech>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace tool_messageinbound\privacy;
+defined('MOODLE_INTERNAL') || die();
+
+use context;
+use context_user;
+use core_privacy\local\metadata\collection;
+use core_privacy\local\request\approved_contextlist;
+use core_privacy\local\request\transform;
+use core_privacy\local\request\writer;
+
+/**
+ * Data provider class.
+ *
+ * @package    tool_messageinbound
+ * @copyright  2018 Frédéric Massart
+ * @author     Frédéric Massart <fred@branchup.tech>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class provider implements
+    \core_privacy\local\metadata\provider,
+    \core_privacy\local\request\plugin\provider {
+
+    /**
+     * Returns metadata.
+     *
+     * @param collection $collection The initialised collection to add items to.
+     * @return collection A listing of user data stored through this system.
+     */
+    public static function get_metadata(collection $collection) {
+
+        $collection->add_database_table('messageinbound_messagelist', [
+            'messageid' => 'privacy:metadata:messagelist:messageid',
+            'userid' => 'privacy:metadata:messagelist:userid',
+            'address' => 'privacy:metadata:messagelist:address',
+            'timecreated' => 'privacy:metadata:messagelist:timecreated',
+        ], 'privacy:metadata:messagelist');
+
+        // Arguably the keys are handled by \core\message\inbound\address_manager and thus could/should be handled by core.
+        $collection->add_subsystem_link('core_userkey', [], 'privacy:metadata:coreuserkey');
+
+        return $collection;
+    }
+
+    /**
+     * Get the list of contexts that contain user information for the specified user.
+     *
+     * @param int $userid The user to search.
+     * @return \contextlist $contextlist The contextlist containing the list of contexts used in this plugin.
+     */
+    public static function get_contexts_for_userid($userid) {
+        $contextlist = new \core_privacy\local\request\contextlist();
+
+        // Always add the user context so we're sure we're not dodging user keys, besides it's not costly to do so.
+        $contextlist->add_user_context($userid);
+
+        return $contextlist;
+    }
+
+    /**
+     * Export all user data for the specified user, in the specified contexts.
+     *
+     * @param approved_contextlist $contextlist The approved contexts to export information for.
+     */
+    public static function export_user_data(approved_contextlist $contextlist) {
+        global $DB;
+        if (!static::approved_contextlist_contains_my_context($contextlist)) {
+            // We only care about the user's user context.
+            return;
+        }
+
+        $userid = $contextlist->get_user()->id;
+        $context = context_user::instance($userid);
+        $path = [get_string('messageinbound', 'tool_messageinbound')];
+
+        // Export user keys.
+        \core_userkey\privacy\provider::export_userkeys($context, $path, 'messageinbound_handler');
+
+        // Export the message list.
+        $data = [];
+        $recordset = $DB->get_recordset('messageinbound_messagelist', ['userid' => $userid], 'timecreated, id');
+        foreach ($recordset as $record) {
+            $data[] = [
+                'received_at' => $record->address,
+                'timecreated' => transform::datetime($record->timecreated),
+            ];
+        }
+        $recordset->close();
+        writer::with_context($context)->export_data($path, (object) ['messages_pending_validation' => $data]);
+    }
+
+    /**
+     * Delete all data for all users in the specified context.
+     *
+     * @param context $context The specific context to delete data for.
+     */
+    public static function delete_data_for_all_users_in_context(context $context) {
+        global $DB;
+        if ($context->contextlevel != CONTEXT_USER) {
+            return;
+        }
+
+        static::delete_user_data($context->instanceid);
+    }
+
+    /**
+     * Delete all user data for the specified user, in the specified contexts.
+     *
+     * @param approved_contextlist $contextlist The approved contexts and user information to delete information for.
+     */
+    public static function delete_data_for_user(approved_contextlist $contextlist) {
+        global $DB;
+        if (!static::approved_contextlist_contains_my_context($contextlist)) {
+            // We only care about the user's user context.
+            return;
+        }
+
+        static::delete_user_data($contextlist->get_user()->id);
+    }
+
+    /**
+     * Delete a user's data.
+     *
+     * @param int $userid The user ID.
+     * @return void
+     */
+    protected static function delete_user_data($userid) {
+        global $DB;
+        $DB->delete_records_select('messageinbound_messagelist', 'userid = :userid', ['userid' => $userid]);
+        \core_userkey\privacy\provider::delete_userkeys('messageinbound_handler', $userid);
+    }
+
+    /**
+     * Return whether the contextlist contains our own context.
+     *
+     * @param approved_contextlist $contextlist The contextlist
+     * @return bool
+     */
+    protected static function approved_contextlist_contains_my_context(approved_contextlist $contextlist) {
+        $userid = $contextlist->get_user()->id;
+        foreach ($contextlist->get_contexts() as $context) {
+            if ($context->contextlevel == CONTEXT_USER && $context->instanceid == $userid) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+}
diff --git a/admin/tool/messageinbound/classes/task/cleanup_task.php b/admin/tool/messageinbound/classes/task/cleanup_task.php
index e8b1c7a1978..fc2c01d9093 100644
--- a/admin/tool/messageinbound/classes/task/cleanup_task.php
+++ b/admin/tool/messageinbound/classes/task/cleanup_task.php
@@ -49,6 +49,7 @@ class cleanup_task extends \core\task\scheduled_task {
      */
     public function execute() {
         $manager = new \tool_messageinbound\manager();
-        return $manager->tidy_old_messages();
+        $manager->tidy_old_messages();
+        $manager->tidy_old_verification_failures();
     }
 }
diff --git a/admin/tool/messageinbound/lang/en/tool_messageinbound.php b/admin/tool/messageinbound/lang/en/tool_messageinbound.php
index 20c1c4774f0..cab10b571e3 100644
--- a/admin/tool/messageinbound/lang/en/tool_messageinbound.php
+++ b/admin/tool/messageinbound/lang/en/tool_messageinbound.php
@@ -94,6 +94,12 @@ $string['onehour'] = 'One hour';
 $string['oneweek'] = 'One week';
 $string['oneyear'] = 'One year';
 $string['pluginname'] = 'Inbound message configuration';
+$string['privacy:metadata:coreuserkey'] = 'User\'s keys to validate the email received';
+$string['privacy:metadata:messagelist'] = 'A list of message identifiers which failed validation and requires further authorisation';
+$string['privacy:metadata:messagelist:address'] = 'The address at which the email was sent';
+$string['privacy:metadata:messagelist:messageid'] = 'The message ID';
+$string['privacy:metadata:messagelist:timecreated'] = 'The time at which the record was made';
+$string['privacy:metadata:messagelist:userid'] = 'The ID of user who need to approve the message';
 $string['replysubjectprefix'] = 'Re:';
 $string['requirevalidation'] = 'Validate sender address';
 $string['name'] = 'Name';
diff --git a/admin/tool/messageinbound/tests/manager_test.php b/admin/tool/messageinbound/tests/manager_test.php
new file mode 100644
index 00000000000..936d99636a0
--- /dev/null
+++ b/admin/tool/messageinbound/tests/manager_test.php
@@ -0,0 +1,97 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Manager tests.
+ *
+ * @package    tool_messageinbound
+ * @category   test
+ * @copyright  2018 Frédéric Massart
+ * @author     Frédéric Massart <fred@branchup.tech>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+global $CFG;
+
+use core_privacy\tests\provider_testcase;
+use core_privacy\local\request\approved_contextlist;
+use core_privacy\local\request\transform;
+use core_privacy\local\request\writer;
+use tool_messageinbound\privacy\provider;
+
+/**
+ * Manager testcase class.
+ *
+ * @package    tool_messageinbound
+ * @category   test
+ * @copyright  2018 Frédéric Massart
+ * @author     Frédéric Massart <fred@branchup.tech>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class tool_messageinbound_manager_testcase extends provider_testcase {
+
+    public function setUp() {
+        global $CFG;
+        $this->resetAfterTest();
+
+        // Pretend the system is enabled.
+        $CFG->messageinbound_enabled = true;
+        $CFG->messageinbound_mailbox = 'mailbox';
+        $CFG->messageinbound_domain = 'example.com';
+    }
+
+    public function test_tidy_old_verification_failures() {
+        global $DB;
+
+        $now = time();
+        $stale = time() - DAYSECS;
+
+        $this->create_messagelist(['timecreated' => $now]);
+        $this->create_messagelist(['timecreated' => $now - HOURSECS]);
+        $this->create_messagelist(['timecreated' => $stale]);
+        $this->create_messagelist(['timecreated' => $stale - HOURSECS]);
+        $this->create_messagelist(['timecreated' => $stale - YEARSECS]);
+
+        $this->assertEquals(5, $DB->count_records('messageinbound_messagelist', []));
+        $this->assertEquals(3, $DB->count_records_select('messageinbound_messagelist', 'timecreated < :t', ['t' => $stale + 1]));
+
+        $manager = new \tool_messageinbound\manager();
+        $manager->tidy_old_verification_failures();
+
+        $this->assertEquals(2, $DB->count_records('messageinbound_messagelist', []));
+        $this->assertEquals(0, $DB->count_records_select('messageinbound_messagelist', 'timecreated < :t', ['t' => $stale + 1]));
+    }
+
+    /**
+     * Create a message to validate.
+     *
+     * @param array $params The params.
+     * @return stdClass
+     */
+    protected function create_messagelist(array $params) {
+        global $DB, $USER;
+        $record = (object) array_merge([
+            'messageid' => 'abc',
+            'userid' => $USER->id,
+            'address' => 'text@example.com',
+            'timecreated' => time(),
+        ], $params);
+        $record->id = $DB->insert_record('messageinbound_messagelist', $record);
+        return $record;
+    }
+
+}
diff --git a/admin/tool/messageinbound/tests/privacy_test.php b/admin/tool/messageinbound/tests/privacy_test.php
new file mode 100644
index 00000000000..5be172c1f4d
--- /dev/null
+++ b/admin/tool/messageinbound/tests/privacy_test.php
@@ -0,0 +1,201 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Data provider tests.
+ *
+ * @package    tool_messageinbound
+ * @category   test
+ * @copyright  2018 Frédéric Massart
+ * @author     Frédéric Massart <fred@branchup.tech>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+global $CFG;
+
+use core_privacy\tests\provider_testcase;
+use core_privacy\local\request\approved_contextlist;
+use core_privacy\local\request\transform;
+use core_privacy\local\request\writer;
+use tool_messageinbound\privacy\provider;
+
+/**
+ * Data provider testcase class.
+ *
+ * @package    tool_messageinbound
+ * @category   test
+ * @copyright  2018 Frédéric Massart
+ * @author     Frédéric Massart <fred@branchup.tech>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class tool_messageinbound_privacy_testcase extends provider_testcase {
+
+    public function setUp() {
+        global $CFG;
+        $this->resetAfterTest();
+
+        // Pretend the system is enabled.
+        $CFG->messageinbound_enabled = true;
+        $CFG->messageinbound_mailbox = 'mailbox';
+        $CFG->messageinbound_domain = 'example.com';
+    }
+
+    public function test_get_contexts_for_userid() {
+        $dg = $this->getDataGenerator();
+        $u1 = $dg->create_user();
+        $u2 = $dg->create_user();
+        $u1ctx = context_user::instance($u1->id);
+        $u2ctx = context_user::instance($u2->id);
+
+        $contexts = provider::get_contexts_for_userid($u1->id)->get_contexts();
+        $this->assertCount(1, $contexts);
+        $this->assertEquals($u1ctx->id, $contexts[0]->id);
+
+        $contexts = provider::get_contexts_for_userid($u2->id)->get_contexts();
+        $this->assertCount(1, $contexts);
+        $this->assertEquals($u2ctx->id, $contexts[0]->id);
+    }
+
+    public function test_delete_data_for_user() {
+        global $DB;
+        $dg = $this->getDataGenerator();
+        $u1 = $dg->create_user();
+        $u2 = $dg->create_user();
+        $u1ctx = context_user::instance($u1->id);
+        $u2ctx = context_user::instance($u2->id);
+
+        $addressmanager = new \core\message\inbound\address_manager();
+        $addressmanager->set_handler('\tool_messageinbound\message\inbound\invalid_recipient_handler');
+        $addressmanager->set_data(123);
+
+        // Create a user key for both users.
+        $addressmanager->generate($u1->id);
+        $addressmanager->generate($u2->id);
+
+        // Create a messagelist for both users.
+        $this->create_messagelist(['userid' => $u1->id]);
+        $this->create_messagelist(['userid' => $u2->id]);
+
+        $this->assertTrue($DB->record_exists('user_private_key', ['userid' => $u1->id, 'script' => 'messageinbound_handler']));
+        $this->assertTrue($DB->record_exists('user_private_key', ['userid' => $u2->id, 'script' => 'messageinbound_handler']));
+        $this->assertTrue($DB->record_exists('messageinbound_messagelist', ['userid' => $u1->id]));
+        $this->assertTrue($DB->record_exists('messageinbound_messagelist', ['userid' => $u2->id]));
+
+        // Passing another user's context does not do anything.
+        provider::delete_data_for_user(new approved_contextlist($u1, 'tool_messageinbound', [$u2ctx->id]));
+        $this->assertTrue($DB->record_exists('user_private_key', ['userid' => $u1->id, 'script' => 'messageinbound_handler']));
+        $this->assertTrue($DB->record_exists('user_private_key', ['userid' => $u2->id, 'script' => 'messageinbound_handler']));
+        $this->assertTrue($DB->record_exists('messageinbound_messagelist', ['userid' => $u1->id]));
+        $this->assertTrue($DB->record_exists('messageinbound_messagelist', ['userid' => $u2->id]));
+
+        // Deleting user 1.
+        provider::delete_data_for_user(new approved_contextlist($u1, 'tool_messageinbound', [$u1ctx->id]));
+        $this->assertFalse($DB->record_exists('user_private_key', ['userid' => $u1->id, 'script' => 'messageinbound_handler']));
+        $this->assertTrue($DB->record_exists('user_private_key', ['userid' => $u2->id, 'script' => 'messageinbound_handler']));
+        $this->assertFalse($DB->record_exists('messageinbound_messagelist', ['userid' => $u1->id]));
+        $this->assertTrue($DB->record_exists('messageinbound_messagelist', ['userid' => $u2->id]));
+    }
+
+    public function test_delete_data_for_all_users_in_context() {
+        global $DB;
+        $dg = $this->getDataGenerator();
+        $u1 = $dg->create_user();
+        $u2 = $dg->create_user();
+        $u1ctx = context_user::instance($u1->id);
+        $u2ctx = context_user::instance($u2->id);
+
+        $addressmanager = new \core\message\inbound\address_manager();
+        $addressmanager->set_handler('\tool_messageinbound\message\inbound\invalid_recipient_handler');
+        $addressmanager->set_data(123);
+
+        // Create a user key for both users.
+        $addressmanager->generate($u1->id);
+        $addressmanager->generate($u2->id);
+
+        // Create a messagelist for both users.
+        $this->create_messagelist(['userid' => $u1->id]);
+        $this->create_messagelist(['userid' => $u2->id]);
+
+        $this->assertTrue($DB->record_exists('user_private_key', ['userid' => $u1->id, 'script' => 'messageinbound_handler']));
+        $this->assertTrue($DB->record_exists('user_private_key', ['userid' => $u2->id, 'script' => 'messageinbound_handler']));
+        $this->assertTrue($DB->record_exists('messageinbound_messagelist', ['userid' => $u1->id]));
+        $this->assertTrue($DB->record_exists('messageinbound_messagelist', ['userid' => $u2->id]));
+
+        // Deleting user 1.
+        provider::delete_data_for_all_users_in_context($u1ctx);
+        $this->assertFalse($DB->record_exists('user_private_key', ['userid' => $u1->id, 'script' => 'messageinbound_handler']));
+        $this->assertTrue($DB->record_exists('user_private_key', ['userid' => $u2->id, 'script' => 'messageinbound_handler']));
+        $this->assertFalse($DB->record_exists('messageinbound_messagelist', ['userid' => $u1->id]));
+        $this->assertTrue($DB->record_exists('messageinbound_messagelist', ['userid' => $u2->id]));
+    }
+
+    public function test_export_data_for_user() {
+        $dg = $this->getDataGenerator();
+        $u1 = $dg->create_user();
+        $u2 = $dg->create_user();
+        $u1ctx = context_user::instance($u1->id);
+        $u2ctx = context_user::instance($u2->id);
+
+        $addressmanager = new \core\message\inbound\address_manager();
+        $addressmanager->set_handler('\tool_messageinbound\message\inbound\invalid_recipient_handler');
+        $addressmanager->set_data(123);
+
+        // Create a user key for both users.
+        $addressmanager->generate($u1->id);
+        $addressmanager->generate($u2->id);
+
+        // Create a messagelist for both users.
+        $this->create_messagelist(['userid' => $u1->id, 'address' => 'u1@example1.com']);
+        $this->create_messagelist(['userid' => $u1->id, 'address' => 'u1@example2.com']);
+        $this->create_messagelist(['userid' => $u2->id, 'address' => 'u2@example1.com']);
+
+        // Export for user.
+        $this->setUser($u1);
+        provider::export_user_data(new approved_contextlist($u1, 'tool_messageinbound', [$u1ctx->id, $u2ctx->id]));
+        $data = writer::with_context($u2ctx)->get_data([get_string('messageinbound', 'tool_messageinbound')]);
+        $this->assertEmpty($data);
+        $data = writer::with_context($u1ctx)->get_data([get_string('messageinbound', 'tool_messageinbound')]);
+        $this->assertCount(2, $data->messages_pending_validation);
+        $this->assertEquals('u1@example1.com', $data->messages_pending_validation[0]['received_at']);
+        $this->assertEquals('u1@example2.com', $data->messages_pending_validation[1]['received_at']);
+
+        $data = writer::with_context($u2ctx)->get_related_data([get_string('messageinbound', 'tool_messageinbound')], 'userkeys');
+        $this->assertEmpty($data);
+        $data = writer::with_context($u1ctx)->get_related_data([get_string('messageinbound', 'tool_messageinbound')], 'userkeys');
+        $this->assertCount(1, $data->keys);
+        $this->assertEquals('messageinbound_handler', $data->keys[0]->script);
+    }
+
+    /**
+     * Create a message to validate.
+     *
+     * @param array $params The params.
+     * @return stdClass
+     */
+    protected function create_messagelist(array $params) {
+        global $DB, $USER;
+        $record = (object) array_merge([
+            'messageid' => 'abc',
+            'userid' => $USER->id,
+            'address' => 'text@example.com',
+            'timecreated' => time(),
+        ], $params);
+        $record->id = $DB->insert_record('messageinbound_messagelist', $record);
+        return $record;
+    }
+
+}