Mozart's widow passed off a Requiem finished by his student as his own and sold it twice

Wolfgang Amadeus Mozart died at 35 with debts and was buried in a common grave at St. Marx, as the burial rules of the time required for most citizens; his body was never identified^†. He left an unfinished Requiem. Count Franz von Walsegg had ordered it anonymously and paid in advance, intending to present it as his own work. His widow, Constanze, needed the balance of the fee. She gave the score to composer Joseph Eybler, who stopped, then to Mozart's student Franz Xaver Süssmayr, who finished it. She delivered it to Walsegg as Mozart's. Despite the exclusive commission, she sold a copy to the King of Prussia in 1792 and later sold copies to publishers Breitkopf & Härtel and Johann Anton André. On 8 November 1799 she signed a contract with André for the Mozart manuscripts in her possession. Breitkopf published the Requiem around 1800. The dispute over which bars are Mozart's and which are Süssmayr's continues in 2026, and new completions are still performed.