Superbridge index of composite knots

An upper bound of the superbridge index of the connected sum of two knots i s given in terms of the braid index of the summands. Using this upper bound and minimal polygonal presentations, we give an upper bound in terms of th e superbridge index and the bridge index of the summands when they are toru s knots. In contrast to the fact that the difference between the sum of bri dge indices of two knots and the bridge index of their connected sum is alw ays one, the corresponding difference for the superbridge index can be arbi trarily large.