An anvil assembly having a tissue contact surface and a plurality of staple pockets formed in the tissue contact surface. Each of the plurality of staple pockets including first and second staple forming cups, each of the first and second staple forming cups having an outside portion and an inside portion, the inside portion of the first and second staple forming cups being positioned in close relation to each other and the outside portion of the first and second staple forming cups being positioned in spaced relation to each other. Each of the first and second staple forming cups being defined by sidewalls and an elongated base surface, wherein upper portions of the sidewalls intersect the tissue contact surface at a line of intersection, and wherein the line of intersection is curved along a majority of its length between the outside portion and the inside portion of each of the staple forming cups.