Sigler To Leave Sony: Arista Dir./National Promotion John Sigler will leave at the end of the month after more than four years in the post and more than eight with the company. No word from Arista regarding plans for the position, but following the departure of Columbia's David Friedman for UMG (Breaking News 8/20), the move leaves each of the Sony imprints with only one National each. Sigler can still be reached at Sony or via his personal email here.