In an embodiment, a semiconductor package includes a semiconductor device embedded in an insulating layer and having a first contact pad at a first surface of the semiconductor device. An outer contact pad is positioned on a lower surface of the insulating layer. A vertical redistribution structure electrically couples the first contact pad to the outer contact pad. The first contact pad has a plurality of first via sites. A first subset of the first via sites is occupied by first vias and a second subset of the first via sites remains unoccupied and forms a first via-free zone, such that the first vias are non-uniformly distributed over the first contact pad.