Temporal evolution of magnetic flux. The magnetic flux of the positive and negative polarity patches identified in Fig. 9 is shown as dotted lines with violet triangles and thick violet lines, respectively. Their scaling is shown on the violet y-axis to the right. The relative magnetic flux of the previously emerged negative-polarity region near the new satellite sunspot is shown as open circles. Black crosses show the positive flux in the satellite spot in the area shown in Fig. 6. The last two quantities are referenced to their values at 10:52 UT.