Mozart symphonies of spurious or doubtful authenticity

In some instances the main body of the work has been entirely lost, its identity being preserved only through an incipit (record of the opening few bars) cataloged by Breitkopf & Härtel, who published the Alte Mozart-Ausgabe (AMA) in 1883.

Cataloging errors based on inadequate information, and an occasional over-eagerness to attribute new discoveries to Mozart has added to the problem.

The original catalogue, known as K1, listed incomplete or lost works in an appendix or "Anhang", without regard to chronological order.

However, as Neal Zaslaw (the editor of K9) pointed out,[7] the K6 allocations between main listing and Anhang are not reliable indicators of authenticity or otherwise.

[7] "Deest"[8] is used to identify works that have not been included in any of the Köchel catalogue versions, but which have at some stage in the past been thought of as Mozart compositions.