'Leck' was a U-boat wolfpack operation, in tandem with 'Isar' and 'Inn', in the Atlantic against the ONS.7 convoy (10/15 May 1943).

The wolfpack comprised U-91, U-202 and U-664, and neither lost any of its own number nor sank any ship before being broken up for incorporation in the 'Donau' wolfpacks.