diff --git a/lib/composer/composer/autoload_classmap.php b/lib/composer/composer/autoload_classmap.php
index 2c962b0fc6d6f..3999e60bfef17 100644
--- a/lib/composer/composer/autoload_classmap.php
+++ b/lib/composer/composer/autoload_classmap.php
@@ -1426,6 +1426,7 @@
     'OC\\Repair\\RepairDavShares' => $baseDir . '/lib/private/Repair/RepairDavShares.php',
     'OC\\Repair\\RepairInvalidShares' => $baseDir . '/lib/private/Repair/RepairInvalidShares.php',
     'OC\\Repair\\RepairMimeTypes' => $baseDir . '/lib/private/Repair/RepairMimeTypes.php',
+    'OC\\Repair\\RepairShareOwnership' => $baseDir . '/lib/private/Repair/RepairShareOwnership.php',
     'OC\\Repair\\SqliteAutoincrement' => $baseDir . '/lib/private/Repair/SqliteAutoincrement.php',
     'OC\\RichObjectStrings\\Validator' => $baseDir . '/lib/private/RichObjectStrings/Validator.php',
     'OC\\Route\\CachingRouter' => $baseDir . '/lib/private/Route/CachingRouter.php',
diff --git a/lib/composer/composer/autoload_static.php b/lib/composer/composer/autoload_static.php
index da591ab0c0ff9..a74e8b00fc9e6 100644
--- a/lib/composer/composer/autoload_static.php
+++ b/lib/composer/composer/autoload_static.php
@@ -1455,6 +1455,7 @@ class ComposerStaticInit53792487c5a8370acc0b06b1a864ff4c
         'OC\\Repair\\RepairDavShares' => __DIR__ . '/../../..' . '/lib/private/Repair/RepairDavShares.php',
         'OC\\Repair\\RepairInvalidShares' => __DIR__ . '/../../..' . '/lib/private/Repair/RepairInvalidShares.php',
         'OC\\Repair\\RepairMimeTypes' => __DIR__ . '/../../..' . '/lib/private/Repair/RepairMimeTypes.php',
+        'OC\\Repair\\RepairShareOwnership' => __DIR__ . '/../../..' . '/lib/private/Repair/RepairShareOwnership.php',
         'OC\\Repair\\SqliteAutoincrement' => __DIR__ . '/../../..' . '/lib/private/Repair/SqliteAutoincrement.php',
         'OC\\RichObjectStrings\\Validator' => __DIR__ . '/../../..' . '/lib/private/RichObjectStrings/Validator.php',
         'OC\\Route\\CachingRouter' => __DIR__ . '/../../..' . '/lib/private/Route/CachingRouter.php',
diff --git a/lib/private/Repair.php b/lib/private/Repair.php
index 91bfd47f5de06..4ebea3f7440e6 100644
--- a/lib/private/Repair.php
+++ b/lib/private/Repair.php
@@ -68,6 +68,7 @@
 use OC\Repair\Owncloud\SaveAccountsTableData;
 use OC\Repair\RemoveLinkShares;
 use OC\Repair\RepairDavShares;
+use OC\Repair\RepairShareOwnership;
 use OC\Repair\RepairInvalidShares;
 use OC\Repair\RepairMimeTypes;
 use OC\Repair\SqliteAutoincrement;
@@ -209,6 +210,7 @@ public static function getRepairSteps() {
 			\OC::$server->get(AddBruteForceCleanupJob::class),
 			\OC::$server->get(AddCheckForUserCertificatesJob::class),
 			\OC::$server->get(RepairDavShares::class),
+			\OC::$server->get(RepairShareOwnership::class),
 			\OC::$server->get(LookupServerSendCheck::class),
 		];
 	}
diff --git a/lib/private/Repair/RepairShareOwnership.php b/lib/private/Repair/RepairShareOwnership.php
new file mode 100644
index 0000000000000..bab3aab91e5e0
--- /dev/null
+++ b/lib/private/Repair/RepairShareOwnership.php
@@ -0,0 +1,91 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2020 Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program 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.
+ *
+ * This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+namespace OC\Repair;
+
+use OCP\IDBConnection;
+use OCP\Share\IManager;
+use OCP\Migration\IOutput;
+use OCP\Migration\IRepairStep;
+
+class RepairShareOwnership implements IRepairStep {
+	private IDBConnection $dbConnection;
+	private IManager $shareManager;
+
+	public function __construct(
+		IDBConnection $dbConnection,
+		IManager $shareManager
+	) {
+		$this->dbConnection = $dbConnection;
+		$this->shareManager = $shareManager;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function getName() {
+		return 'Repair shares ownership';
+	}
+
+	protected function repairWrongShareOwnership(IOutput $output, bool $dryRun = true) {
+		$qb = $this->dbConnection->getQueryBuilder();
+		$brokenShare = $qb
+			->select('s.id', 'm.user_id', 's.uid_owner', 's.uid_initiator', 's.share_with')
+			->from('share', 's')
+			->join('s', 'filecache', 'f', $qb->expr()->eq('s.item_source', 'f.fileid'))
+			->join('s', 'mounts', 'm', $qb->expr()->eq('f.storage', 'm.storage_id'))
+			->where($qb->expr()->neq('m.user_id', 's.uid_owner'))
+			->andWhere($qb->expr()->eq($qb->func()->concat($qb->expr()->literal('/'), 'm.user_id', $qb->expr()->literal('/')), 'm.mount_point'))
+			->executeQuery()
+			->fetchAll();
+
+		foreach ($brokenShare as $queryResult) {
+			$shareId = $queryResult['id'];
+			$initiator = $queryResult['uid_initiator'];
+			$receiver = $queryResult['share_with'];
+			$owner = $queryResult['uid_owner'];
+			$mountOwner = $queryResult['user_id'];
+
+			$output->info("Found share from $initiator to $receiver, owned by $owner, that should be owned by $mountOwner");
+
+			if ($dryRun) {
+				continue;
+			}
+
+			$share = $this->shareManager->getShareById($shareId);
+			$share->setShareOwner($mountOwner);
+			$this->shareManager->updateShare($share);
+		}
+
+		return true;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function run(IOutput $output) {
+		$this->repairWrongShareOwnership($output);
+	}
+}