Étude Op. 25, No. 12 in C minor is the last of Frédéric Chopin's formal studies for the Piano, opus 25, dedicated À Madame la Comtesse d'Agoult. It was first published in 1837 in French, German, and English. In the first French edition, the time signature is 4/4, but most modern editions follow the manuscript and German editions, which indicate cut time. This work is a series of rising and falling arpeggios in various Chord progressions from C minor. In addition, its opening bars recall the chord structure of the opening bars of the second prelude of the first book of The Well-Tempered Clavier by Johann Sebastian Bach.