diff --git a/appinfo/info.xml b/appinfo/info.xml
index 56fbd4834..97ce852b5 100644
--- a/appinfo/info.xml
+++ b/appinfo/info.xml
@@ -70,6 +70,8 @@ Those groups of people can then be used by any other app for sharing purpose.
 		<command>OCA\Circles\Command\MembersDetails</command>
 		<command>OCA\Circles\Command\MembersLevel</command>
 		<command>OCA\Circles\Command\MembersRemove</command>
+
+		<command>OCA\Circles\Command\MigrateCustomGroups</command>
 	</commands>
 
 		<activity>
diff --git a/lib/Command/MigrateCustomGroups.php b/lib/Command/MigrateCustomGroups.php
new file mode 100644
index 000000000..7d293e1a3
--- /dev/null
+++ b/lib/Command/MigrateCustomGroups.php
@@ -0,0 +1,256 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Circles\Command;
+
+use OC\Core\Command\Base;
+use OCA\Circles\CirclesManager;
+use OCA\Circles\Exceptions\CircleNotFoundException;
+use OCA\Circles\Exceptions\FederatedItemException;
+use OCA\Circles\Exceptions\FederatedUserException;
+use OCA\Circles\Exceptions\FederatedUserNotFoundException;
+use OCA\Circles\Exceptions\InvalidIdException;
+use OCA\Circles\Exceptions\MemberNotFoundException;
+use OCA\Circles\Exceptions\OwnerNotFoundException;
+use OCA\Circles\Exceptions\RemoteInstanceException;
+use OCA\Circles\Exceptions\RemoteNotFoundException;
+use OCA\Circles\Exceptions\RemoteResourceNotFoundException;
+use OCA\Circles\Exceptions\RequestBuilderException;
+use OCA\Circles\Exceptions\SingleCircleNotFoundException;
+use OCA\Circles\Exceptions\UnknownRemoteException;
+use OCA\Circles\Exceptions\UserTypeNotFoundException;
+use OCA\Circles\IFederatedUser;
+use OCA\Circles\Model\FederatedUser;
+use OCA\Circles\Model\Member;
+use OCP\DB\Exception;
+use OCP\DB\QueryBuilder\IQueryBuilder;
+use OCP\IConfig;
+use OCP\IDBConnection;
+use OCP\Share\IShare;
+use Psr\Log\LoggerInterface;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+
+class MigrateCustomGroups extends Base {
+	private OutputInterface $output;
+	/** @var IFederatedUser[] */
+	private array $fedList = [];
+
+	public function __construct(
+		private CirclesManager $circlesManager,
+		protected IDBConnection $connection,
+		protected IConfig $config,
+		private LoggerInterface $logger,
+	) {
+		parent::__construct();
+	}
+
+	protected function configure() {
+		parent::configure();
+		$this->setName('circles:migrate:customgroups');
+	}
+
+	protected function execute(InputInterface $input, OutputInterface $output): int {
+		$this->output = $output;
+		if (!$this->shouldRun()) {
+			$this->output->writeln('migration already done or table \'custom_group\' not found');
+			return 0;
+		}
+
+		$this->migrateTeams();
+		$this->config->setAppValue('circles', 'imported_custom_groups', 'true');
+
+		return 0;
+	}
+
+	public function migrateTeams(): void {
+		$this->output->writeln('Migrating custom groups to Teams');
+
+		$owners = $this->extractCustomGroupsAndOwners();
+
+		// we get list of all custom groups
+		$queryCustomGroups = $this->connection->getQueryBuilder();
+		$queryCustomGroups->select('group_id', 'display_name', 'uri')
+						  ->from('custom_group')
+						  ->orderBy('group_id');
+
+		$resultCustomGroups = $queryCustomGroups->executeQuery();
+
+		// we cycle for each custom group
+		while ($rowCG = $resultCustomGroups->fetch()) {
+			$groupId = $rowCG['group_id'] ?? 0;
+			$groupUri = $rowCG['uri'] ?? '';
+			$ownerId = $owners[$groupId] ?? '';
+			if ($ownerId === '' || $groupId === 0) {
+				continue; // if group or owner is not know, we ignore the entry.
+			}
+
+			// based on owner's userid, we create federateduser and a new circle
+			$this->output->writeln('+ New Team <info>' . $rowCG['display_name'] . '</info>, owner by <info>' . $ownerId . '</info>');
+			$owner = $this->cachedFed($ownerId);
+
+			$this->circlesManager->startSession($owner);
+			$circle = $this->circlesManager->createCircle($rowCG['display_name']);
+
+			// we get all members for this custom group
+			$queryMembers = $this->connection->getQueryBuilder();
+			$queryMembers->select('user_id', 'role')
+						 ->from('custom_group_member')
+						 ->where($queryMembers->expr()->eq('group_id', $queryMembers->createNamedParameter($groupId)));
+
+			$members = [$ownerId];
+			$resultMembers = $queryMembers->executeQuery();
+			while ($rowM = $resultMembers->fetch()) {
+				$userId = $rowM['user_id'];
+				// if admin, ignore
+				if ($userId === '') {
+					continue;
+				}
+
+				try {
+					$members[] = $userId;
+					if ($userId === $ownerId) {
+						continue; // owner is already in the circles
+					}
+
+					$this->output->writeln(' - new member <info>' . $userId .'</info>');
+					$member = $this->circlesManager->addMember($circle->getSingleId(), $this->cachedFed($userId));
+					if ($rowM['role'] === '1') {
+						$this->circlesManager->levelMember($member->getId(), Member::LEVEL_ADMIN);
+					}
+				} catch (\Exception $e) {
+					$this->output->writeln('<error>' . get_class($e) . ' ' . $e->getMessage() . '</error>');
+					$this->logger->log(2, 'error while migrating custom group member', ['exception' => $e]);
+				}
+			}
+
+			$this->circlesManager->stopSession();
+			$resultMembers->closeCursor();
+
+			$this->updateShares($groupUri, $circle->getSingleId(), $members);
+			$this->output->writeln('');
+		}
+
+		$resultCustomGroups->closeCursor();
+	}
+
+	/**
+	 * - type 7 instead of 1
+	 * - with circle ID instead of `customgroup_` + group URI
+	 * - update children using memberIds
+	 *
+	 * @param string $groupUri
+	 * @param string $circleId
+	 * @param array $memberIds
+	 *
+	 * @throws Exception
+	 */
+	public function updateShares(string $groupUri, string $circleId, array $memberIds): void {
+		$shareIds = $this->getSharedIds($groupUri);
+
+		$update = $this->connection->getQueryBuilder();
+		$update->update('share')
+			   ->set('share_type', $update->createNamedParameter(IShare::TYPE_CIRCLE))
+			   ->set('share_with', $update->createNamedParameter($circleId))
+			   ->where($update->expr()->in('id', $update->createNamedParameter($shareIds, IQueryBuilder::PARAM_INT_ARRAY)));
+
+		$count = $update->executeStatement();
+		$this->output->writeln('> ' . $count . ' shares updated');
+
+		$this->fixShareChildren($shareIds, $memberIds);
+	}
+
+	/**
+	 * manage local cache FederatedUser
+	 *
+	 * @param string $userId
+	 * @return FederatedUser
+	 */
+	private function cachedFed(string $userId): FederatedUser {
+		if (!array_key_exists($userId, $this->fedList)) {
+			$this->fedList[$userId] = $this->circlesManager->getLocalFederatedUser($userId);
+		}
+
+		return $this->fedList[$userId];
+	}
+
+	/**
+	 * update share children using the correct member id
+	 *
+	 * @param string $shareId
+	 * @param array $memberIds
+	 */
+	private function fixShareChildren(array $shareIds, array $memberIds): void {
+		$update = $this->connection->getQueryBuilder();
+		$update->update('share')
+			->set('share_type', $update->createNamedParameter(IShare::TYPE_CIRCLE))
+			->set('share_with', $update->createParameter('new_recipient'))
+			->where($update->expr()->in('parent', $update->createNamedParameter($shareIds, IQueryBuilder::PARAM_INT_ARRAY)))
+			->andWhere($update->expr()->eq('share_with', $update->createParameter('old_recipient')));
+
+		$count = 0;
+		foreach($memberIds as $memberId) {
+			$update->setParameter('old_recipient', $memberId);
+			$update->setParameter('new_recipient', $this->cachedFed($memberId)->getSingleId());
+			$count += $update->executeStatement();
+		}
+
+		$this->output->writeln('> ' . $count . ' children shares updated');
+	}
+
+
+	private function getSharedIds(string $groupUri): array {
+		$select = $this->connection->getQueryBuilder();
+		$select->select('*')
+			   ->from('share')
+			   ->where($select->expr()->eq('share_type', $select->createNamedParameter(IShare::TYPE_GROUP)));
+
+		$shareIds = [];
+		$result = $select->execute();
+		while ($row = $result->fetch()) {
+			$with = $row['share_with'];
+			if (!str_starts_with($with, 'customgroup_')
+				|| substr($with, strlen('customgroup_')) !== $groupUri) {
+				// not a custom group, or not the one we're looking for
+				continue;
+			}
+
+			$shareIds[] = $row['id'];
+		}
+
+		return $shareIds;
+	}
+
+	protected function shouldRun(): bool {
+		$alreadyImported = $this->config->getAppValue('circles', 'imported_custom_groups', 'false');
+		return $alreadyImported === 'false' && $this->connection->tableExists('custom_group') && $this->connection->tableExists('custom_group_member');
+	}
+
+	/**
+	 * returns owners for each custom groups
+	 *
+	 * @return array<string, string> [groupId => userId]
+	 * @throws Exception
+	 */
+	private function extractCustomGroupsAndOwners(): array {
+		$queryOwners = $this->connection->getQueryBuilder();
+		$queryOwners->select('group_id', 'user_id')
+					->from('custom_group_member')
+					->where($queryOwners->expr()->eq('role', $queryOwners->createNamedParameter('1')));
+
+		$resultOwners = $queryOwners->executeQuery();
+		$owners = [];
+		while ($rowO = $resultOwners->fetch()) {
+			// no idea if custom groups in owncloud can hold multiple 'owner'
+			$owners[$rowO['group_id']] = $owners[$rowO['group_id']] ?? $rowO['user_id'];
+		}
+		$resultOwners->closeCursor();
+
+		return $owners;
+	}
+}
diff --git a/lib/Migration/ImportOwncloudCustomGroups.php b/lib/Migration/ImportOwncloudCustomGroups.php
deleted file mode 100644
index cd0ef3dba..000000000
--- a/lib/Migration/ImportOwncloudCustomGroups.php
+++ /dev/null
@@ -1,209 +0,0 @@
-<?php
-/**
- * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
- * SPDX-License-Identifier: AGPL-3.0-or-later
- */
-
-namespace OCA\Circles\Migration;
-
-use OCA\Circles\Model\DeprecatedCircle;
-use OCA\Circles\Model\DeprecatedMember;
-use OCP\IConfig;
-use OCP\IDBConnection;
-use OCP\Migration\IOutput;
-use OCP\Migration\IRepairStep;
-use OCP\Share;
-
-/**
- * Class ImportOwncloudCustomGroups
- *
- * @package OCA\Circles\Migration
- */
-class ImportOwncloudCustomGroups implements IRepairStep {
-	/** @var IDBConnection */
-	protected $connection;
-
-	/** @var  IConfig */
-	protected $config;
-
-	/** @var array */
-	protected $circlesById = [];
-	/** @var array */
-	protected $circlesByUri = [];
-	/** @var array */
-	protected $circleHasAdmin = [];
-
-	public function __construct(IDBConnection $connection, IConfig $config) {
-		$this->connection = $connection;
-		$this->config = $config;
-	}
-
-	/**
-	 * Returns the step's name
-	 *
-	 * @return string
-	 * @since 9.1.0
-	 */
-	public function getName() {
-		return 'Fix the share type of guest shares when migrating from ownCloud';
-	}
-
-	/**
-	 * @param IOutput $output
-	 */
-	public function run(IOutput $output) {
-		if (!$this->shouldRun()) {
-			return;
-		}
-
-		$this->createCircles($output);
-		$this->createMemberships($output);
-		$this->updateShares($output);
-
-		$this->config->setAppValue('circles', 'imported_custom_groups', 'true');
-	}
-
-	/**
-	 * @param IOutput $output
-	 */
-	public function createCircles(IOutput $output) {
-		$output->info('Creating circles');
-
-		$select = $this->connection->getQueryBuilder();
-		$select->select('*')
-			->from('custom_group')
-			->orderBy('group_id');
-
-		$insert = $this->connection->getQueryBuilder();
-		$insert->insert('circle_circles')
-			->values([
-				'name' => $insert->createParameter('name'),
-				'type' => $insert->createParameter('type'),
-				'creation' => $insert->createFunction('NOW()'),
-			]);
-
-		$output->startProgress();
-		$result = $select->execute();
-
-		while ($row = $result->fetch()) {
-			$insert->setParameter('name', $row['display_name'])
-				->setParameter('type', DeprecatedCircle::CIRCLES_CLOSED);
-
-			$insert->execute();
-			$output->advance();
-
-			$this->circlesById[$row['groud_id']] = $insert->getLastInsertId();
-			$this->circlesByUri[$row['uri']] = $this->circlesById[$row['groud_id']];
-		}
-
-		$result->closeCursor();
-		$output->finishProgress();
-	}
-
-	/**
-	 * @param IOutput $output
-	 */
-	public function createMemberships(IOutput $output) {
-		$output->info('Creating memberships');
-
-		$select = $this->connection->getQueryBuilder();
-		$select->select('*')
-			->from('custom_group_member')
-			->orderBy('group_id');
-
-		$insert = $this->connection->getQueryBuilder();
-		$insert->insert('circle_members')
-			->values([
-				'circle_id' => $insert->createParameter('circle_id'),
-				'user_id' => $insert->createParameter('user_id'),
-				'level' => $insert->createParameter('level'),
-				'status' => $insert->createParameter('status'),
-				'joined' => $insert->createFunction('NOW()'),
-			]);
-
-		$output->startProgress();
-		$result = $select->execute();
-
-		while ($row = $result->fetch()) {
-			if (!isset($this->circlesById[$row['group_id']])) {
-				// Stray membership
-				continue;
-			}
-
-			$level = (int) $row['role'] === 1 ? DeprecatedMember::LEVEL_OWNER : DeprecatedMember::LEVEL_MEMBER;
-
-			if ($level === DeprecatedMember::LEVEL_OWNER) {
-				if (isset($this->circleHasAdmin[$this->circlesById[$row['group_id']]])) {
-					$level = DeprecatedMember::LEVEL_MODERATOR;
-				} else {
-					$this->circleHasAdmin[$this->circlesById[$row['group_id']]] = $row['user_id'];
-				}
-			}
-
-			$insert->setParameter('circle_id', $this->circlesById[$row['group_id']])
-				->setParameter('user_id', $row['user_id'])
-				->setParameter('level', $level)
-				->setParameter('status', 'Member');
-
-			$insert->execute();
-			$output->advance();
-		}
-
-		$result->closeCursor();
-		$output->finishProgress();
-	}
-
-	/**
-	 * Update shares
-	 * - type 7 instead of 1
-	 * - with circle ID instead of `customgroup_` + group URI
-	 *
-	 * @param IOutput $output
-	 */
-	public function updateShares(IOutput $output) {
-		$output->info('Update shares from custom groups to circles');
-
-		$select = $this->connection->getQueryBuilder();
-		$select->select('*')
-			->from('share')
-			->where($select->expr()->eq('share_type', $select->createNamedParameter(Share::SHARE_TYPE_GROUP)));
-
-		$update = $this->connection->getQueryBuilder();
-		$update->update('share')
-			->set('share_type', $update->createParameter('type'))
-			->set('share_with', $update->createParameter('with'))
-			->where($update->expr()->eq('id', $update->createParameter('id')));
-
-		$output->startProgress();
-		$result = $select->execute();
-
-		while ($row = $result->fetch()) {
-			$with = $row['share_with'];
-			if (strpos($with, 'customgroup_') !== 0) {
-				// Stray membership
-				continue;
-			}
-
-			$groupUri = substr($with, strlen('customgroup_'));
-			if ($groupUri === '' || !isset($this->circlesByUri[$groupUri])) {
-				// Not a customgroup
-				continue;
-			}
-
-			$update->setParameter('type', Share::SHARE_TYPE_CIRCLE)
-				->setParameter('with', $this->circlesByUri[$groupUri])
-				->setParameter('id', $row['id']);
-
-			$update->execute();
-			$output->advance();
-		}
-
-		$result->closeCursor();
-		$output->finishProgress();
-	}
-
-	protected function shouldRun() {
-		$alreadyImported = $this->config->getAppValue('circles', 'imported_custom_groups', 'false');
-		return !$alreadyImported && $this->connection->tableExists('custom_group') && $this->connection->tableExists('custom_group_member');
-	}
-}