There is a very unusual feature to this concerto. In addition to omitting the tempi for two of the movements, Mozart also, in Tyson's words, "did not write any notes for the piano's left hand in a great many measures throughout the work." As can be seen in the Dover Publications facsimile, large stretches of the solo part simply have nothing at all for the left hand, including the opening solo (mvmt. I, mm. 81–99) and the whole of the second movement. There is in fact no other Mozart piano concerto of which so much of the solo part was left unfinished by the composer.