Contrapunctus 14 starts with all four voices in the common way, dux, comes, dux, comes (tonica, dominant, tonica, dominant). This is followed by the inverse. The first partition ends at bar 115. The theme and the inverse develop three times to the parallel, at bar 22, 44, 73. The first partition has a regular division of the theme at the prime, octave and undecime, see figure 16.
Figure 15. Themes of Contrapunctus 14
The second partition consists of bar 115 to 193, the second theme is introduced. Again the start is in the common way dux, comes, dux, comes. Three times the first and second theme are combined, first in the combinations prime-octave (interval an octave), the second combination in the parallel, and inverted at the octave and the third combination in the dominant with the first theme in stretto.
The regular division is at the fifth.
In the third partition, the third theme is introduced, the start is again in the common way dux, comes, dux, comes followed by a combination with the inverse of the first theme. The regular division is in the octave and the fourth. The third partition is short and there isn’t a development to the parallel. With the exception on page 5, the third theme isn’t combined with the other themes. This is remarkable because the third theme is the harmonizing one.
Looking overall, the structure is a regular division of the inverse of the theme at the duodecime. These appear at bar 80, 100 and 213.